Thursday, December 31, 2015

Fitness Research For 2015

Picture by Elliot Brown from Flickr
As the year draws to a close, I looked back at all the articles I've read and I realise that there were many articles written by research scientists on exercise and brain health this year. 

One of the more persistent themes seems to be that in order to live long, age well and maintain both a nimble and sharp mind we need to be physically active. Many of the new studies demonstrated previously unexplored ways in which exercise helps our brains and minds.

Exercise, usually running seems to increase the number of neurons in our brains and helps sharpen thinking skills and mood as we age.

Fortunately the exercise periods needed seems to be much shorter than we expect

One article I read on brain imaging was really interesting. A group of Japanese researchers found that the brains of fit older men were almost as efficient as the brains of young people. 

The researchers found that the aerobically fit older men's brains used fewer resources during thinking compared to the out of shape men of the same age. This is similar to someone fitter using less energy to perform a physical task compared to someone less fit. 

So at least for me personally, a good reason to keep running regularly to make sure my brain stays sharp.

Another study looked at whether and how weight training and muscles affect the brain. Healthy, older women who completed the year long, twice weekly weight training sessions of light weight training showed fewer and smaller brain lesions in their brain's white matter compared to women of the same age who only completed a stretching/ balance training session or going to the gym once a week.

White matter connects and passes messages to different parts of the brain, which is crucial for memory and thinking.

While I was still training and competing, I used to go to the gym thrice weekly. Since 2009, I haven't at all. Looks like I may have to introduce some weight training/ resistance exercise in the coming new year. 

I do have some heavy tiles/ drain covers in my back garden which I've hauled around before so I don't have to weed the garden so often. Believe me, they're heavy too. I may have my own "nature gym"in my back garden after all ......



So here's wishing all our readers, patients and friends a great year ahead in 2016.

References

Bolandzadeh N, Tam R et al (2015). Resistance Training And White Matter Lesion Progression In Older Women: Exploratory Analysis Of A 12-Month Randomized Controlled Trial. J Am Geriatr Soc, 63(10): pp 2052-2060. DOI: 10.1111/jgs.13644.

Hyodo K, Dan I et al (2015). The Association Between Aerobic Fitness And Cognitive Function In Older Men Mediated By Frontal Lateralization.NeurolImage. 125: pp 289-230. DOI:10.1016/j.neurolimage.2015.09.062.

Tuesday, December 22, 2015

Muscle Wasting Occurs Quickly

Check out the difference in size.
Have a look at my patient's legs in the picture above. See the difference in size? Can you guess how quickly it happened?

My patient fell while skiing in Japan and the doctor there said she tore her medial collateral ligament (MCL). She was prescribed crutches, a huge brace and came back in a wheelchair.

There was definite swelling around her knee and I taped it to reduce the swelling of course and promptly taught her how to walk without the crutches and wheelchair.

2 days. that's how quickly the muscle atrophy took place.

Later an MRI confirmed she tore her MCL as well as her anterior cruciate ligament (ACL) as well.


Monday, December 14, 2015

Your GPS Watch May Be Overestimating Your Mileage

Picture by link_alicante from Flickr
Recently one of my patients mentioned that a particular race he finished seemed to be longer based on the reading on his GPS (global positioning system) watch. He said that he did not run the corners in the race at the widest bend nor did he weave in and out while overtaking other runners. Neither did he take a wrong turn during the race. He was upset that a certified course was "inaccurate" according to his GPS watch.

Well, recently I happened to chance upon an article on how distances are measured via GPS watch/ phones etc and I told him what I read.

A GPS device can measure distance as orbiting satellites communicate with your watch/ smartphone that you run or walk with.  The communication is not continuous but a frequent "check in". While running or walking, your GPS device collects a GPS track. A GPS track consists of a sequence of consecutive GPS positions.

The GPS device does not monitor your movement continuously, it monitors your location at specific times and then measures distances between each location. Potentially, this leads to two types of errors.

The first error is the interpolation error. If the GPS watch/ phone you run with does not show your position frequently enough, it will underestimate the distance you ran.

The second error is a measurement error. Each time the satellite tries to pick your location, it can be slightly off. When your watch/ phone tries to measure your position between your last two positions, the distance will be inaccurate.These tiny errors add up the longer you run.

Hence, if your GPS watch collects too many locations as you run, your distance tracked will be longer. If not enough positions are collected your run distance measured will be shorter,

For this study, the researchers had their subject walk on a pre measured track using a a GPS device that tracked positions every second. A very low quality GPS device was used deliberately as they wanted the error to be visible. The researchers noted that with a better quality device the error will be less but will still be present.

As technology improves, these errors will be minimised though.

I've never owned a GPS watch and have never ran with one so far. Looks like I probably don't have too.

Reference

Ranacher P, Brunauer R et al (2015). Why GPS Makes Distances Bigger Than They Are. Int J Georg Info Sci. DOI: 10.1080/13658816.2015.1086924.

Friday, December 4, 2015

Oakley Jawbreaker


My Christmas present from Oakley came early this year. They were sent to me by courier earlier this afternoon. Many thanks to Joey from Oakley.

I was supposed to get a pair of the Jawbreaker in June during the Sea Games, but since I'm no longer competing and Oakley needed to give our Team Singapore athletes priority I just got it.

Well, better late than never.

Noticed that the Jawbreaker has adjustable earpieces. This is great since the ear pieces of some other models of Oakley sometimes get in the way of the helmet fastening/ adjustment straps. Lens clarity looks superb

Adjustable length for the ear pieces
Lens clarity looks superb while trying it so far, I'll find out while riding tomorrow.

Monday, November 30, 2015

How Much Should You Run In A Week?

This is the little guy I run with mostly now
I often get asked by my patients if I'm still training or how much I still bike or run etc. I tell them that I'm definitely not training seriously like before. I still swim occasionally and bike (if cycling my son to school is included). And I usually just run back after working at Physio Solutions twice a week. (For those who want to know- I take a bus there).

So I'm happy to read that a recently published review suggested that running a few miles a week can substantially improve your health. The authors specifically reviewed journals published in PubMed since 2000 that had a sample size of at least 500 runners and a 5-year follow up period.

The researchers found that you do not need to run a whole lot to get benefits. How much are we talking about here?

Based on the latest published evidence reviewed, the authors suggest that running 20 to 30 minutes or about one and a half to three miles (2.4 to 4.8 km) twice a week appears to be perfect.

Even with such low mileage, runners generally weighed less and and had a lower risk of obesity compared to people who did not exercise. The runners were also less likely to have high blood pressure, high cholesterol levels, diabetes, strokes, certain cancers and arthritis compared to non-runners, or those who ran less than five miles a week.

The authors also suggested that running a few additional miles will help if you need better weight control and it "allows one to eat more calories".

Those who are looking to be faster and better runners will definitely need to run more although some evidence suggest that running strenuously for more than an hour every day could slightly increase your risk for heart problems, running related injuries and disabilities.

Reference

Lavie CJ, Lee DC et al (2015). Effects Of Running On Chronic Diseases And Cardiovascular And All-cause Mortality. Mayo Clin Proce. 90(11): 1541-52. DOI: 10.1016/j.mayocp.2015.08.001.

*Thanks to Rachel Wong for helping me get the article.

Monday, November 23, 2015

Feels Good But May Be Unhealthy


I have always been a poor sleeper. Even when I was training very hard. In fact when I pushed myself too hard at training, I usually found it harder to fall asleep. And I could never sleep in. My internal body clock is set such that I could never sleep past 7 am.

Turns out not being able to sleep in may not be such a bad thing after all.

A group of researchers studied 447 men and women between the ages of 34 to 54. They wore devices that tracked movement and also monitored them when they slept and woke.

Nearly 85 percent of the group went to sleep and woke later on their off days compared to during their work days.

The researchers found that the greater the mismatch in sleep timing between their week days and week ends the higher the metabolic risk.

Sleeping late on off days (week ends) was linked to lower HDL (or good) cholesterol, higher triglycerides, higher insulin resistance and a higher body mass index. This is true even after adjusting for physical activity, caloric intake, alcohol intake and other factors.

The researchers are not sure if this is similar in the long term as the subjects were only studied for seven days. Several other studies have shown that there is an association between shift work and in increased risk for heart disease and diabetes, similar to what this study has shown.

Don't stay up too late on your off days.


Reference

Wong PM, Hasler BP et al (2015). Social Jetlag, Chrontype And Cardiometabolic Risk. J of Clin Endo and Metabolim. DOI: http://dx.doi.org/10.1210/jc.2015-2923.

Sunday, November 15, 2015

Running Injuries? Blame Your Genes?

Chromosome by Hey Paul Studios from Flickr
All right, it's finally been proven, some people are more prone to injury than others. So says a newly published article from the British Journal of Sports Medicine.

The researchers found evidence from family and genetic studies that DNA sequence variants (together with non-genetic factors) can increase your risk for tendon and ligament injuries. This is for both exercise-associated and occupational-associated acute and chronic injuries to tendons and ligaments.

Although research at this stage is still preliminary, there have been specific gene variants found (COL5A1 gene) that are less likely (58 percent less) to cause Achilles tendinopathy (degenerative change in the tendon).

A different gene (COL1A1) is associated with ACL (anterior cruciate ligament) and Achilles tendon ruptures (September et al, 2009).

In fact, several other genes have been associated with injuries ranging from carpal tunnel to tennis elbow.

The common link among these genes is that they affect collagen fibrils structure. Collagen fibrils are the basic structural building block for tendons, ligaments and other connective tissue including fascia. In simple terms, some Achilles tendons are built better than others.

So what do you do with this information then? Athletes and coaches beware, especially when there are now many genetic tests marketed for self testing promising to reveal potential injury susceptibilities.

The researchers reported that such tests should be requested by an appropriately qualified healthcare professional since results need to be interpreted together with certain clinical indicators and other lifestyle factors.

Personally I'm fairly sceptical about such over the counter/ online genetic tests that you can purchase to do a self test on whether you're more prone to injury.

Will knowing that really change your training habits? As a previously compulsive competitive athlete, I trained as hard as I could handle and more without getting injured. Knowing I'm say, 10-20 percent more likely to get a tendon injury will not alter my day to day training. On the contrary, because I've been training hard for so long (previously), I know what injuries I'm prone to because I've already had them previously.

Hmmm, maybe from now I'll ask my patients whether they have a family history of tendon or ligament injuries instead. (Standard practice for Physiotherapists is asking patients if they have any family history of hypertension, heart diseases and cancer etc).


Reference

Collins M, September AV and Posthumus M (2015). Biological Variation In Musculoskeletal Injuries: Current Knowledge, Future Research And Practical Limitations. BJSM. DOI: 10.1136/bjsports-2015-095180.

September AV, Cook J et al (2009). Variants Within The COL5A1 Gene Are Associated With Achilles Tendinopathy In Two Populations. BJSM. 43: 357-365. DOI: 10.1136/bjsm.2008.048793.

Thursday, November 5, 2015

Recovering From Bangkok Bomb Blast ST 051115

Straits Times (051115)
Sports Solutions is featured in the Straits Times today. One of our patients recovering after being injured on August 17 this year in the Erawan Shrine at the Rachprasong section in Bangkok while on holiday there with his family.

We wish him well for his recovery.

It's in the Straits Times today on page B10.

Hydrotherapy

Sunday, November 1, 2015

Running After Total Hip Replacement

Picture by Cindy Funk from Flickr
I've had a patient who came in to our clinic this past week asking if she can still run after surgery as she was considering a hip replacement. Another patient recently had hip replacement surgery and wanted to get back to running quickly.

I told both of them what I knew was that under laboratory testing conditions, more pounding translates into shorter lifespans for artificial joints. That means when you load your joint more (after hip replacement surgery) during running, the artificial joint will wear out more rapidly than someone who participates in lower impact activities such as cycling or swimming.

Adverse effects could mean dislocations, fractures, loosening of the prosthesis and scraping off and scattering within the body of metal fragments.

In a 2014 study, researchers investigated 23 adults who returned or started running after hip replacement surgery reported few problems five years after their surgery. There was very little evidence that their subjects experienced the above mentioned adverse effects.

Theirs was quite a small group of subjects and the follow up period was relatively short too.

In another larger study, 804 hips from 608 patients were investigated. Among the subjects who ran (an average of four times a week covering 3.6 km), none of the subjects had any loosening, abnormal implant migration or excessive wear during the five year follow up as well.

I suggested to my patient (who had the hip replacement done) that she shouldn't rush back to running after surgery. She needs to regain full range of motion in the hip and get the muscles around the joint strong first before attempting to run. Of course I suggested deep water running/ aqua based rehabilitation first.


References

Abe H, Sakai T et al (2014). Jogging After Total Hip Arthroplasty. Am J Sp Med. 42(1): 131-137. DOI: 10.1177/0363546513506866.

Meira EP and Zeni J Jr (2014). Sports participation Following Total Hip Arthoplasty. Int J Sports Phys Ther. 996): 839-850.

Sunday, October 25, 2015

Maybe You Didn't Exercise Hard Enough?

Picture by Irving Henson from The Pit
I've got some friends who really love eating and some of them have been complaining to me that exercise just doesn't seem to work for them. Despite exercising regularly they seem to be packing on the pounds still.

Maybe you didn't exercise hard enough? That was the first thing that came to mind when they asked for my thoughts on that matter. Granted, I know not everyone responds the same way to a certain exercise program. Turns out I may be right when I recently came across the following article.

Researchers studied 121 sedentary and obese adults who exercised five times a week over a duration of 24 weeks.

The subjects were split into three groups. A low intensity, low duration group who did moderate walking (31.2 minutes of exercise at 50 percent VO2 max). The second group exercised at low intensity but longer duration (57.9 minutes of exercise at 50 percent VO2 max). The final group did a higher intensity, longer duration of brisk walking (39.7 minutes at 75 percent VO2 max).

After four weeks there were "non-responders" across all three groups. Non responders were those whose fitness levels did not improve.

The number of "non-responders" decreased as the weeks passed although they remained in the low intensity groups. There was however, no "non'-responders" in the high intensity group, meaning everyone in that group got fitter.

The researchers suggested that there will not be any "non-responders" as long as they exercised hard enough for long enough.

Hard enough in this study basically involved brisk walking, meaning you may need to do more if you're younger and fitter.

Reference

Ross R, de Lannoy L and Stotz PJ (2015). Separate Effects Of Intensity And Amount Of Exercise On Interindividual Cardiorespiratory Fitness Response. Mayo Clinic Proceedings. pii: S0025-6196(15)00640-0. DOI: 10.1016/j.mayocp.2015.07.024.

Walk this way! (Picture by Irving Henson from The Pit

Friday, October 16, 2015

What About Energy Return In Your Running Shoes?

How many of you recognize this shoe? Reebok ERS 5000- from 1988
Runners, don't you want running shoes that not only protect your feet but give you energy as you go?
It seems that many shoe companies are joining the energy return movement again. Why did I say again?

Well, looking at the picture above, how many of you will know what I'm talking about if I mention "ERS"? To be specific, the Reebok ERS or energy return system technology Reebok came up with in 1988 to compete with the Nike Air technology. That was way back in 1988!

Let me sidetrack a little. The ERS comprises of a series of cylinders made from Dupont Hytrel placed in the midsole of the shoe to act as springs. This was meant to help propel the runner forward after foot strike or so Reebok claims. (Note - ERS was phased out when Reebok invented Hexalite their next technology). Come talk to me if you wanna discuss shoe technology from the 80's and 90's.
The Adidas Boost
In the present day, there's Adidas claiming its Boost midsole material will "keep every step charged with an endless supply of light, fast energy." Puma's IGNITE foam says "Energy in. More energy out." Saucony tells you its new Everun foam will give you "increased energy return" and a "lively underfoot sensation."

When a running shoe cushions well, it also lowers the responsive response of that shoe (since it has to absorb the force). A responsive shoe means firmness in that shoe and that firmness allows you to transfer the force from your stride into running faster.

And cushioning and responsiveness are mutually exclusive. Either you have a shoe that is soft and cushions your landing by dissipating that energy or a shoe that allows your to put your energy directly into propulsion.

These new energy return shoes try to combine the two properties. They absorb more than the previous traditional foam used in running shoes and then store that energy that was absorbed to return the foam to original shape quickly producing a responsive feel as they push back on the bottom of your foot during push off.

Despite what the ads say, no material can actually produce energy that can propel your next running step. No foam can actually do that. The basic law of physics states that no system creates or destroys energy. Energy can only be transformed. If anything, what energy that is returned tends to be generated by your own stride in the first place.

Even if the foam did bounce back harder than it was compressed, it is unlikely it can propel you in any meaningful way. This is because running involves forces generated by your muscles, joints, tendons and bones along with gravity and friction. In order to get that "energy return", the energy has to be returned at the right time, frequency and right location (Nigg, 2010). It just doesn't happen so easily.

The running shoe industry has yet to get all these variables working together, regardless whether the rebound is from foam, tubes, springs or mechanical trampolines used by Newton, Spira or any other brand currently.

Moreover, the current energy return foam is fairly heavy. Weight has a large impact on running shoes. Previous studies show that for every 100 grams (or 3.5 ounces) added to your foot, energy cost is increased by one percent. This is also why you want to use racing flats when you race as a lighter shoe allows your foot to turnover faster and thus leading to faster race times.

If you have tried some of these newer "energy return" shoes though, you just might be sold on them. They actually feel fantastic when you first try them on. One of my patients who's tried it said his feet felt like a million dollars. But like I always say, it's the legs (and running technique) that makes you fast not the shoes.

Previous studies have shown that your own muscles and tendons and a good running technique will reduce overall impact forces better than the midsole of your running shoe can. What is important in the cushioning of the shoe is spreading the load across your foot. This may explain why those who switched to minimalist/ barefoot running type shoes had no more knee or hip pain but ended up with stress fractures on their metatarsals (or foot bones) instead. This of course lead to a huge outcry against such minimalist/ barefoot running type shoes.

So, now you know that getting energy return or propulsion is not so straight forward and not something you should expect from a shoe. Not yet anyway.

References

Liberman DE, Venkadesan et al (2010). Foot Strike Patterns And Collision Forces In Habitually Barefoot Versus Shod Runners. Nature. Jan 463(7280): 531-535.

Nigg BM (2010). Biomechanics Of Sports Shoes. Calgary, Alta. : University of Calgary, c2010.

Sunday, October 11, 2015

How To Prevent Age Related Running Speed Loss

Now that's a strong calf
It's a sad fact but true. As a runner, you get slower as you age. This is partly due to the weakening of muscles around your ankles and calves according to a recently published article.

The article looked at a whole range of variables across a wide range of runners. The runners studied ranged from age 23 to 59 years old. The runners were filmed running at their normal pace on a treadmill with a high speed video camera.

The older runners in the study maintained the same stride frequency as the younger runners (about 83 strides/ minute). The one glaring difference was that they had a much shorter stride length, which the authors felt reduced their running speed.

Stride length and running speed decreased by about 20 percent from age 20 to 59. Ankle power also dropped by almost 48 percent during the same time frame leading the researchers to conclude that runners could probably maintain their running speed by increasing their calf muscle strength and power.

The authors suggested that strengthening the gastrocnemius and soleus muscles (which make up the calf muscles) will benefit runners. They suggested using a combination of slow reps but with heavy weight workouts and faster but using lower weight power workouts to strengthen the calf and to stave off the slowdown.

The authors were also impressed that the runners managed to maintain their weight through the decades and suggested that long term running could be an effective way to maintain weight without medication.

Personally, I feel that if you ran with good technique, you won't need to strengthen your calves. Look at the Kenyans and the Ethiopians that win all the big races all over the world, have they got big strong calves?

Reference

DeVita P, Fellin RE et al (2015). The Relationships Between Age And Running Biomechanics. Med Sci Sports Ex. Epub. DOI: 10.1249/MSS.0000000000000744.

Here's another look - thanks to Vinny for the pictures

Friday, October 2, 2015

Don't Try Anything New On Race Day

Elid Kipchorge and his shoes
I was away on holiday this past week after teaching the Kinesio Taping Level 1-2 course over the week end and did not have regular internet access at where I was.

Having just returned, am catching up on all my mail and news and I came across the results from the recently concluded 2015 Berlin marathon.

Eliud Kipchorge ran and won in a personal best time of 2:04:01 hours in a pair of prototype shoes that malfunctioned!!

According to reports, Kipchorge started having problems with his prototype Nike Air Streak 6 barely just a kilometre into the race. He bravely ran on even after the insoles popped out at the 20 kilometre mark forcing him to run the remaining 22 kilometres with flapping insoles.

Look in your own running shoes and you will find a insole (or sock liner) which is usually easily removed and can be replaced by your own custom orthotic if needed.  They are normally fairly secure and I've never seen them come off during a run (or a race for that matter). Racing flats usually have flatter and thinner inserts that are often glued down and not easily removed.

He ended up with blisters on his left foot and a cut on his big toe with lots of blood.

Remembering he was a sponsored athlete, he added with good PR skills "We have talked with technicians and even the highest authority of the (Nike) company. They are resourceful people. Remember, in life, challenges must be present and I urge my fans to run to Nike stores and grab this version immediately when it's out".

Ethiopian running legend Haile Gebrselassie joked tongue-in-cheek that Nike shoes would never be better than his preferred brand of Adidas. Maybe that's why Gabrselassie joked about it, as Kipchorge was previously sponsored by Adidas.

As you've often heard from me, don't try anything new on race day. I've learnt the hard way before too. Now that's a different post.

Talking about the Nike Air Streaks, I owned a pair of the first version way back in 1997. You can see it below.
The original Air Streak

Sunday, September 27, 2015

Day 2 Of Kinesio Taping Level 1-2 (270915)

Day 2 of the Kinesio Taping Level 1-2 course starts with some questions on how tape left overnight felt on the participants. The participants discussed why there were good or adverse reactions.

After clearing doubts on KT 1, we moved on to Day 2's program on the six Corrective techniques and also on EDF (epidermis, dermis fascia) taping.

The EDF taping concepts and techniques were not taught in many earlier courses so the participants were all ears.

Here are some pictures from Day 2.

Feet together now
Ram's head ? Looks like seagull to me 
Class picture 

Saturday, September 26, 2015

Treating Bertrand's Hip Made His Shoulder Better

Other than treating patients, I like teaching too (sometimes). To make sure I can answer all the questions I get, I need to put in extra effort to keep myself updated and it keeps me on my toes. I always like to keep improving myself.

Now that I probably cannot become a better athlete, I try to make my patients better quicker. And teach better too. And I get to meet other people too.

Spending time explaining biotensegrity
And we do have foreign participants as well from Indonesia (Sports doctor) and from Malaysia of course. Even Elaine from Tunku Abdul Rahman University College who previously attended my Introduction to Kinesio Taping course in Malaysia came for this course.

Elaine in her Cleopatra pose today
Check this out, I found a picture of Elaine from nearly two years ago when I taught the Introduction to Kinesio Taping course in Malaysia.

Here's Elaine in the same pose in KL in November 2013
Here's the practical that threw everyone off. After explaining "biotensegrity" and the "onion tree" model, I demonstrated how treating Betrand's hip made his shoulder better????

Taping Bertrand's hip
And making his shoulder better
Stay tuned for tomorrow's KT 2.

Sunday, September 20, 2015

Probiotics Improve Running Performance?

What my son eats
My wife came down with a bad bug three weeks ago. Then my seven month old infant caught it. I was next. I had a pretty sore throat and was running a temperature. My schedule was fully booked with patients, so I reckon I still had to go to work. I had to take Arcoxia twice to bring my fever down.

I'm actually allergic to Panadol and NSAID's (non steroidal anti inflammatories), but for some strange reason, I can take Arcoxia for my fever with no allergic reactions. I woke up a few mornings later feeling strange in my stomach ........ NSAID's can really mess with the healthy bacteria in my stomach.

Eating your meals too quickly, sports drinks and popping pain medication (or NSAIDs) and life stresses can also decrease the amount of healthy bacteria in your gut as you've found out from my story above.

For those of you who also train hard, the heavy training wears down your immune system and increases your chance of falling ill or picking up an infection. Especially when recovering from a hard workout.

So can improved gut health make you a better runner?

A study on a small group of runners in the European Journal of Applied Physiology showed that their run time to exhaustion in the heat improved by 14 percent after taking probiotics for four weeks. Now that's really relevant to us in hot and sunny Singapore.

Another study showed a 50 percent reduction in the incidence of upper respiratory and gastrointestinal symptoms in elite rugby union players.

Most studies recommend their subjects taking probiotics twice a day. The off season is a good time to experiment with different food and brands of pills you may wanna try. It usually takes about 14 days for probiotics to start working.

You can find them in yogurt, kefir, sauerkraut or in Yakult (for those in Singapore, although it also has lots of sugar).

So don't look at probiotics as a performance enhancer. What it can do is to keep you healthier so you can train better.

Prebiotics help too. Prebiotics are nondigestable fibre compounds that help beneficial bacteria thrive in your intestine. Bananas, asparagus and garlic are good sources of prebiotics.

It is also found in breast milk, Hmmmm, my wife is still breast feeding my seven month old son......


References

Shing CM, Peake JM et al (2014). Effects Of Probiotics Supplementation On Gastrointestinal Permeability, Inflammation And Exercise Performance In The Heat. Eur J Appl Physiol. 11491): 93-103. DPO: 10.10.1007/s00421-013-2748-y.

Haywood BA, Black KE et al (2014). Probiotic Supplementation Reduces The Duration And Incidence Of Infections But Not Severity In Elite Rugby Union Players. J Sci Med Sport. 17(4) 356-360. DOI: http://dx.doi.org/10.1016/j.jsams.2013.08.004.

If you like popping pills

Sunday, September 13, 2015

Carbs With Your Paleolithic Diet?

Picture by Lord Jim from Flickr
I've previously written on the Paleolithic or caveman diet before, which typically consists of hunted meats and fish and food that can be gathered like eggs, insects, fruits, seeds plants and herbs etc.

As a result you're supposed to get healthier, low fat protein, healthier fats and much less dairy and grain (or carbohydrates) than what we normally eat today.

A recent published article however suggests that the Paleo diet did in fact consist of lots of starchy carbohydrates.

The researchers put together information from genetics, archaeology, physiology and nutrition to come up with a theory that our Paleolithic ancestors did actually eat starchy plants like potatoes and possibly even cooking them over fires.

They also suggested that eating carbs help made our brains larger. Without carbs, we may be very different today. We may also not be runners like we can be now.

The authors wrote that carbohydrates are essential for long distance running which is how our ancestors chased down and captured prey. We get energy from glycogen stored n our bodies during vigorous exercise. Our glycogen stores normally lasts about 20 miles (or 32 km) and if you don't eat or drink, you'll hit the wall.

Even evolutionary biologist Daniel Liberman, who has written so much about humans and barefoot running said "The idea that people shouldn't eat carbohydrates is just silly, we've been eating carbohydrates for a long time."

Lieberman however isn't convinced that carbs helped Paleo hunters run better. His research suggested that Paleo hunters who chased down their prey didn't have to run that fast as they actually walked and ran. At those speeds (to keep up with a wounded prey usually) they may not need a lot of carbohydrates. Their bodies probably used more fat instead.

I've written before that relying on fat may help running performance. This is especially true if you have trained your body to use fat as fuel (which our bodies have plenty). It allows us to run further without hitting the wall.

Some have proposed that this may be better for ultra marathon distances (since you tend to run slower). However as speed increases, carbohydrates tend to be vital, especially if you want to run long and fast, suggested Lieberman.

Do take note that the carbs our Paleo ancestors ate were complex carbohydrates and not the overly processed and refined carbohydrates we get on supermarket shelves today.

The authors suggested that we need to be careful when trying to replicate ancestral diets as we still do not know exactly what Paleo man ate.

Looks like you can and should eat complex carbs, especially if you wanna race long and fast.

Reference

Hardy K, Brand-Miller J et al (2015). The Importance Of Dietary Carbohydrate In Human Evolution. The Quarterly Review Of Biology. 90(3): 251-268. DOI. 10.1086/682587.

Cavemen and dinosaurs? by Orln Zebest from Flickr

Sunday, September 6, 2015

Men Do Get It

Picture by German Tenorlo from Flickr
Mention osteoporosis and usually what comes to mind is that someone has fragile or brittle bones and that someone is usually female. If I'm a guy I don't have to worry about it.

It will probably shock you then that estimates in America show that almost two million men have osteoporosis and 16 million men have osteopenia (bone density that is lower than normal but not low enough to be considered osteoporotic). The contributing factors are not doing correct exercises and ageing.

Medication can help improve bone health but recent studies show that strength training and jumping exercises are a healthy alternative.

Researchers studied a group of osteopenic men for a year comparing the effects of weight training and jumping exercises. Both groups of participants completed 60-120 minutes of targeted exercises each week.

The jumping exercises included jump squats, forward hops, split squats, box jumps and depth jumps. The weight training group did squats, modified dead lifts, lunges and calf raises with weights.

Both groups also took calcium and a vitamin D supplement during the study period.

Six months into the research, both groups of men had a significant increase in whole body bone mass, including the lumbar spine (low back) and they maintained the increases for 12 months.

The weight lifting group also had a significant increase in hip bone density. At the end of the study, all the participants had sufficient vitamin D.

The participants also reported low pain and fatigue suggesting that the exercises have good compliance rates and can be easily adapted in a real life setting.

The researchers concluded that targeted exercise with the correct supplements are an effective way to improve bone density rates to reduce risk of developing osteoporosis in men.

Reference

Hinton PS, Nigh P et al (2015). Effectiveness Of Resistance Training Or Jumping-exercise To Increase Bone Mineral Density in Men With Low Bone Mass: A 12-month Randomized, Clinical Trial. Bone. 79: 203-212. DOI: 10.1016/j.bone.2015.06.008.

Monday, August 31, 2015

Latest Research On The ITB (Iliotibial Band)


Picture taken from my Canon Ixus 
Mention the ITB (or iliotibial band) and images of pain quickly crop up. IT band syndrome is a painful overuse injury usually at the lateral (or outer) portion of the knee in many runners and cyclists.

Latest research on the IT band from Daniel Lieberman's Harvard lab by his former student Carolyn Eng shows that the IT band may not function as what was formerly believed.

Another view
The ITB runs along the outer part of the thigh, originating from your Tensor Fascia Lata and Gluteus Maximus muscles just above your hip to attach just below the knee. It is made up of fascia, an elastic connective tissue found throughout our body. Fascia is a sheath of connective tissue that wraps our muscle, nerves and blood vessels. It also connects our muscles to bones.

The researchers used human cadavers to investigate how the IT band moves and stretches during walking and running. A computer model was then built to calculate the forces and strains involved and then compared to the equivalent structure in chimpanzees (published in another journal).

Previously, the IT band's primary function was believed to stabilize the hip during walking. Carolyn Eng's research suggested that the IT band actually acts like a spring, storing energy when you swing your leg back and releasing it as the leg swings forward.

This energy storage capacity is highly developed in humans, enabling it to store 15 to 20 times more energy than a comparable structure in chimpanzees.

Lieberman suggested that if we consider evolution and how humans are adapted not just for walking but running as well, then the IT band is looked at at a totally different perspective. The IT band looked like another elastic structure, similar to the Achilles tendon, and this may be important for saving energy during walking and especially running.

The researchers estimate the IT band stores about seven joules of energy during fast running compared to about the standard estimate of about 50 joules in the Achilles tendon.

The researchers hope that with this improved standing of how the IT band works, they can compare how much forces the IT band transmits in runners with and without IT band pain. This will then establish a scientific basis for treating IT band injuries.

References

Eng CM, Arnold AS, Liberman DE et al (2015). The Capacity Of The Human Iliotibal Band To Store Elastic Energy During Running. J Biomech. pii: S0021-9290 (15) 00354-1. DOI:10.1016/j.jbiomech.2015.06.017.

Eng CM, Arnold AS et al (2015). The Human Iliotibila Band Is Specialized For Elastic Energy Storage Compared With The Chimp Fascia Lata. J Exp Biol. 218(15): 2382-2393. DOI: 10.1242/jeb.117952.


Here's Carolyn Eng's (Harvard University) computer simulation of a human leg running from here.

Wednesday, August 26, 2015

Bike Intervals Can Help You Run Faster

Our training machines
Looks like you gotta spend some time riding furiously on your (stationary) bike if you wanna run faster. All you need is 15 minutes to spare.

A recent study showed that with the right kind of high intensity training on a stationary bike, you can run faster.

The researchers tested runners on a treadmill with a 3 km time trial and split them into four groups. Three groups trained on a stationary bike for two weeks in addition to their regular running routine while a control group just maintained their regular running routine.

The runners did six interval sessions on the stationary bikes in all. Each runner completed six 10-seconds all out efforts. Each group varied the amount of rest between intervals. Rest ranged between 30 seconds to 80 seconds to two minutes rest for the runners. Including warm up and cool down, the session took less than fifteen minutes.

The results showed that the group with the shortest period of rest had the best results. The 30 seconds rest group ran about three percent (or about 25 seconds) faster!

Both the 80 seconds and two minute rest groups did not have any significant improvement in the 3 km time trial. There was no change in the control group.

The researchers attributed the improvement in performance to the elevated heart rate in the 30 second rest group. The short rest prevented the runners from recovering fully making each successive interval more difficult. Their muscles had to adapt faster to the increased load which helped them run faster in the subsequent time trial.

The authors recommend this workout as cross training to avoid injuries. Since stationary cycling also reduced training volume, it is a time efficient way of training as well. Runners who are injured can use this to maintain their fitness while recuperating.

When the weather does not permit you to run outside, you can still ride.

Reference

Kavaliauskas M et al (2015). High-intensity Cycling Training: The Effect Of Work-to-rest Intervals On Running Performance Measures. J Str Cond Research. 29(8): 2229-2236. DOI: 10.1519/JSC.0000000000000868.

Pedaling furiously while it was raining outside
My wife pedaling furiously 5 weeks after giving birth

Sunday, August 16, 2015

Running And Cancer

Picture by Eric Norris from Flickr
The common cold and flu and not the only illnesses that running can ward off. A running (or exercise) strengthened immune system can reduce the likelihood of a variety of illnesses, including many types of cancer.

A large Swedish study found that men who walked or cycled for at least 30 minutes a day had a 34 percent lower risk of dying of cancer compared to couch potatoes.

Researchers studying studying prostate cancer tumour growth in rats that exercise or were sedentary found that rats (like humans) divert blood flow to muscles when exercising. The researchers found a 200 percent increase in tumour blood flow during exercise.

When a tumour is flooded with oxygen, it's activity tends to slow (Jones et al, 2010). This actually leads to a rate of decelerated metastasis (spread of disease to other organs)

Another study by a different group of researchers showed that aerobic exercise leads to tissue returning to it's pre tumour state or ward off development of a more aggressive and dangerous cancer.

Greater blood flow and oxygen delivery to a tumour can possibly transport cancer fighting therapy to the tumour. Exercise increases blood flow by increasing blood pressure and pumping and by decreasing blood vessel constriction.

Exercise is also believed to help reduce cancer by other mechanisms. High insulin levels are associated with increased risk of cancer, and exercise helps reduce insulin levels. There are definitely other mechanisms by which exercise combats cancer that have not been discovered.

You don't have to wait to know these mechanisms to be discovered to get the cancer suppressing benefits of being a runner.

References

McCullough DJ, Nguyen LM et al (2013). Effects Of Exercise Training On Tumor Hypoxia And Vascular Function In The Rodent Preclinical Orthotopic Prostate Cancer Model. J Appl Physiol (1985). 115(12): 1846-54. DOI: 10.1152/japplphysiol.00949.2013.

McCullough DJ, Stabley JN et al (2014). Modulation Of Blood Flow, Hypoxia, And Vascular Function In Orthotopic Prostate Tumours During Exercise. J Natl Cancer Inst. 106(4): dju036. DOI: 10.1093/jnci/djuo36.

Orsini N, Mantzoros CS et al (2008). Association Of Physical Activity With Cancer Incidence, Mortality, And Survival: A Population-based Study Of Men. Br J Cancer. 98: 1864-1869. DOI: 10.1038/sj.bjc.6604354.

Jones LW, Viglianti BL et al (2010). Effect Of Aerobic Exercise On Tumor Physiology In An Animal Model Of Breast Cancer. J Appl Physiol (1985). 108(2): 343-348. DOI: 10.1152/japplphysiol.00424.2009.

Monday, August 10, 2015

Sports Drinks Cannot Replace Your Sodium Levels During Exercise


Gatorade- thirst quencher, but can it replace your sodium levels?
Last week I wrote about what causes muscle cramps. I also said I will write about why the Sports drink/ fluid replacement companies are inaccurate in telling us that sports drinks like Gatorade, Powerade and Endurox etc. can replace electrolyte losses.

When you sweat, your electrolyte levels begin to rise! Yes, you read correctly. Let me explain more.

Let's say you have five cups of water and five teaspoons of salt in your system. If you remove one cup of water and a teaspoon of salt, the balance remains the same. There is a teaspoon of salt for every cup of water (i.e. a concentration of 1.0).

Now if you lose 2 cups of water (like when you exercise) and a teaspoon of salt, you've lost more water than salt. The concentration of salt has now risen to 1.25. Your salt (and electrolyte) levels are now higher and will remain higher as you become more dehydrated.

Apply this concept to our physiology. Our sodium (salt) concentration of blood is about 140 mM (or 3.2 grams of salt in every litre of blood). Our sweat has a sodium concentration between 20-50 mM. So even for "salty sweaters" (people who lose more salt than others when they sweat), they lose about 1.1 grams of salt max in every litre of sweat.

Thus, the theory that muscle cramping is caused by low electrolytes as a result of sweating cannot be true. You definitely lose more fluid (or water) than sodium when you sweat.

Sports drinks are incapable of maintaining your body's sodium levels during exercise despite what the manufacturers and advertisers tell you. The sports drink industry has created a perception  that its electrolytes that will help prevent a decrease in sodium.

As explained above, sweating does not decrease your sodium levels, it causes an increase in sodium levels. Sports drinks actually contain insufficient sodium to counteract the effects of sweating on the blood's electrolyte concentration. In fact it causes your sodium levels to fall further.

A sports drink usually contains approximately 18mM of sodium (or 0.4 grams of sodium per litre). That means if you drink a litre of Gatorade (or 100 plus, Powerade etc) during exercise, you can replace a litre of fluid, but only 0.4 grams of sodium.

Blood normally has 1.4 grams of sodium per litre, so even a sports drink replaces more water relative to salt and will only lower your sodium concentration. You CANNOT elevate or even maintain your sodium levels by drinking a sports drink. It is impossible.

Of course if the alternative to sports drink is water, then sports drinks can help prevent sodium levels from falling further.

The key point is that a sports drink will still cause a decline in sodium levels, though less compared to water.

The act of drinking is what causes the reduction. To prevent your sodium levels for dropping further, you're better off not over drinking in the first place.

It's better to listen to your body and obey what it suggests you to do.

Now you know.

References

Science of Sport - Sports drinks, sweat and electrolytes Part 1

Science of Sport Muscle cramps Part IV

Dugas J (2006). Sodium Ingestion And Hyponatraemia: Sports Drinks Do Not Prevent A Fall In Serum Sodium Concentration During Exercise BJSM. 40: 377. DOI: 10.1136/bjsm.2005.022400.


Sports drinks we have in Singapore
If I have to, I prefer Pocari- "tastiest" to me

Sunday, August 2, 2015

What Causes Muscle Cramps?

Picture by Jon Candy from Flickr
A patient came in to see me yesterday and complained  that if not for a muscle cramp near the end of her recent race, she would have won her age group and also gotten a personal best timing.

After putting it up on Facebook, she had many, many unsolicited comments : Eat bananas, take salt tablets, drink Gatorade, have some pretzels. Knowing that I used to race, she wanted to know my thoughts and get some advice on what else but how not to cramp during a race.

While her friends and even strangers who posted on her Facebook page meant well, none of their advice will help her as even expert exercise physiologists can't say for sure what causes exercise induced cramps.

The most common and popular theory on cramps is that they are caused by sodium (or salt) loss and dehydration. Fluid and electrolyte loss. This has been the focus of much Gatorade (or other companies) sponsored research. More on that in another post definitely.

Tim Noakes, possibly the most renown sports scientist on this topic found no significant differences in sodium and magnesium levels of 72 ultra marathoners between those who cramped and those who didn't cramp. There was no differences in body weight, plasma (or blood) volume between the two groups, showing that dehydration had no real effect on cramps.

Dehydration could however hasten muscle fatigue. And this is what Noakes and most exercise scientists believe is the likely cause of cramps.

In the above ultra marathoner study, 100 percent of the runners cramped in the last half of the race or right after the race. Think about it, when was the last time you had a muscle cramp? At mile 20 (or 32 km) in a marathon or after 3 km in a 5 km race?

This explains why cramping is most likely to occur during races than training. You tend to start off too fast or you pushed yourself too hard. Other studies have found that tough, hilly course and poor pacing (starting too fast) are predictive of muscle cramps.

So, anything you can do to prevent muscle fatigue should then help to prevent cramps. The obvious though undesirable strategy is to simply slow down. Not what you would want to hear or read!

Since guarding against muscle fatigue is key, you can't take any short cuts in training. Train more, do longer distances. You simply have to adapt to the distance you want to race. There is no substitute for strength work that is running specific. Gotta love hills and speed work.

Plyometrics (or explosive exercises) may improve the endurance of the receptors in your muscles that are thought to cause muscle cramps.

Knowing your own capabilities is key as you can choose a pace right from the onset of the race. Cramps are more likely to happen to athletes who start too fast.

"That's it"? My patient said. Yes, that's it.

Reference

Schwellnus MP, Nichol J, Laubscher R and Noakes T. (2004). Serum Electrolyte Concentrations And Hydration Status Are Not Associated With Exercise Associated Muscle Cramping (EAMC) In Distance Runners. BJSM. 38: 488-492. DOI: 10.1136/bjsm.2003.007021.

Sunday, July 26, 2015

Ice Vest Improve Your Race Performance?

Cooling vests by Cozy winters
You may have seen elite athletes (like Alberto Contador above) donning an ice vest prior to their events and wondered if that really helps. Well they do, but a recent study showed that precooling your legs may be much more effective (than an ice vest) before a race in hot, humid conditions.

The researchers had their runners complete three randomized 5 km time trials on a treadmill in a laboratory at about 90 degrees Fahrenheit (about 32.2 degrees Celsius) and close to 50 percent humidity.

The runners did a 30 minute warmup consisting of jogging, static and dynamic stretches, more jogging and some short strides to finish.

One group of runners did warmup with an ice vest and another with ice packs covering the thighs (the researchers developed shorts with pockets on the front and back of each high to hold frozen gel packs). The third group was a control group with no cooling devices.

The runners' core and skin temperature, heart rates, perceived rates of exertions were measured during the time trials. Runners with ice packs on their thighs ran the 5 km 85 seconds faster than the control group. Those with the ice vests ran 45 seconds quicker than the control group.

The 5 km times in the study were a lot slower than the runners' own personal bests (19:30 on average compared to 23:45 min after the thigh pre cooling). The authors suggested that this was due to the hot conditions, the fact that the runners could control their pace on the treadmill and that they were not in a race environment.

The authors suggested improvements even in cooler conditions, down to 70 degrees Fahrenheit (or 21.1 Celsius).

The authors cautioned that not everyone will shave 85 seconds off their 5 km race times if you employ such a strategy before your next race in the heat, but there will be some level of benefit.

This study is unique as the runners performed an active, sport specific warmup before the race to mimic what runners actually do before a race.

The authors suggest using an elastic bandage over frozen gel packs on your thighs as an alternative to ice shorts or vests.

Oh, and remember to drink a slushie too.

Reference

Randall CA, Ross EZ et al (2015). Effect Of Practical Precooling On Neuromuscular Function And 5-km Time-trial Performance In Hot, Humid Conditions Amonh Well-trained Male Runners. J Strength Cond Research. 29(7): 1925-1936. DOI: 10.1519/JSC.0000000000000840.

From Amazon

Sunday, July 19, 2015

Protein Before Bed Builds Muscle

Night time snack before zzzzz
You can't simply build muscle eating lots of protein. To build muscle you need a combination of resistance training and protein. Recent studies show that the most effective way to trigger muscle growth is to spread your protein intake in several doses of 20-25 grams throughout the day.

A group of researchers have previously demonstrated that if you consume protein right before sleeping it can increase the rate protein synthesis (the process of making protein) by 22 percent during overnight recovery from exercise.

This same group of researchers now wanted to know if consuming protein before bed would increase the muscle adaptive response to weight training.

They did a 12 week double blinded study on a bunch of volunteers who weight trained three times a week. The subjects drank either a protein drink or placebo before bed. The protein drink contained 27.5 grams of protein and 15 grams of carbs.

The results showed that the group that had the protein drink had significantly greater improvements in muscle strength, muscle size and even muscle fiber size (done by muscle biopsy).

The subjects were already consuming diets that were fairly high in protein (1.3 grams/kg) and they also had a protein snack (10 grams of protein) after each workout.

How should you snack up on your pre bedtime meal? A cup of low fat milk has about eight grams of protein, and if you had some toast and peanut butter that will probably do the trick.

Don't forget to weight train too.

Reference

Snijders T, Res PT et al (2015). Proten Ingestion Before Sleep Increases Muscle Mass And Strength Gains During Prolonged Exercise Training In Healthy Young Men. J Nutri. 145(6): 1178-1184. DOI: 10.3945/jn.114.208371.

Sunday, July 12, 2015

How Much Water To Drink After Exercise?

Picture by Daniel Orth from Flickr
I was reading a paper on the 24-hour hydration status in runners after a dehydrating run and testing what measurements are reliable to detect this when I thought of a very funny thing that happened at the Olympics.

As Team Singapore's Physiotherapist at the Beijing 2008 Olympics, other than treating the athletes, I was sometimes roped in to help test our Singaporean athletes' hydration status (since we only had one nutritionist and no exercise physiologist at the games).

Director of High Performance and other senior management at Singapore Sports Council (now SSI) decided that in order to perform well and/ or win medals, our athletes needed to be amply hydrated at all times.

Some of our athletes complained about this rather strongly as they were asked to drink more water when their hydration status showed that they needed more fluids. These athletes complained that after consuming more water they had to get up in the middle of the night to pee and afterwards could not fall asleep again for a long time.

You know what they did? They simply added water to their urine samples to pass the hydration test. Our staff got their testing done, the athletes got their much deserved sleep. No names will be mentioned to protect the athletes involved.

Anyway, back to the study.

The group of runners in the study ran in hot conditions until they lost about three percent of their starting weight on three occasions. The three rehydration protocol was either 3.2, 4.2 or 5.2 litres of fluid over the next 24 hours.

Rehydration in the first 24 hours were assessed by measuring body weight of the runners, urine colour, urine specific gravity (a measure of urine concentration) and reported thirst sensation.

The most sensitive marker for fluid consumption during the first 12 hours was urine specific gravity. (Atago - which measures devices to measure specific urine specificity was used and they also sponsored this study).

Thirst emerged as a very sensitive and reliable marker by the end of the 24 hour period. The problem is that differences in thirst did not appear after the run but only emerged the next morning so you may go to bed not knowing you've not drunk enough water.

When the runners drank a lot, they urinated more, when the drank less, they urinated less. You may be surprised with this but when food and fluid intake were tightly controlled, the runners' body weight was unable to detect low fluid intake. The researchers concluded that body weight wasn't a particularly helpful way of tracking how much you're drinking.

There were only subtle changes in urine colour when measured on the researchers 8-point scale. So you have to pay close attention to the shade of your urine colour should you choose to to use this cue.

4.2 litres corresponded to replacing about 100 percent of the sweat losses within the first 12 hours of their run and 200 percent within 24 hours. This was sufficient to return the runners to normal by the time they were ready to run again the next day.

Turns out it corresponded most closely to how much the runners would have normally drunk too.


Reference

O'Neal EK, Stevenson MC et al (2015). Hydration Assessment Technique Over 24-h Post-run With Low, Moderate, And High Fluid Replacement. ACSM Annual Meeting. May 28, 2015. Abstract here.

With the then Singapore President at the 2008 Olympics

Sunday, July 5, 2015

Blood Poisoning In Extreme Endurance Events

Picture by orangefan_2011 from Flickr
If you haven't trained hard enough for your upcoming marathon or ultra marathon race, beware for there may be more adverse effects than you think.

Extended exercises beyond four hours can put your body at risk if you are not sufficiently prepared. Stomach bacteria may seep into your bloodstream and cause poisoning.

Two different studies looked at runners taking part in two different ultra distance races in Scotland (between 78-130 miles) and Spain (5-day 143 miles stage race).

Before and after the races, blood samples were taken from the runners and a control group not racing.

Blood markers in most of the runners after the races showed traces of blood poisoning. This was similar to what you see if you were admitted to the hospital for food poisoning. Almost all the runners had stomach issues during the race as well. None were hospitalized though.

Some runners even had blood markers resembling those who have sepsis - a potentially life threatening illness where chemicals released into the bloodstream to fight infection actually generate heavy inflammation.

This happens when blood moves away from the stomach area to the working muscles when we exercise. This causes the stomach wall to spread apart and leave open gaps. Endotoxins (naturally occurring bacteria in the stomach) fit through these gaps and leach into the blood. This activates an inflammatory response in the body.

Usually the body can easily clean up this sort of bacteria leaching. Only under heavy duress the body can be overwhelmed. This can occur in extreme exercise conditions, heat stress, illness and infection.

When the weather is hot, blood flow away from the stomach to the working muscles will be more extreme, so strategies to keep the body cool during training and racing is critical.

The researchers added that repeated bouts of inflammation like this can cause long term fatigue, stomach problems and immune disturbances.

What was interesting was that in both studies, runners who trained sufficiently had higher levels of Interleukin-10, a small anti inflammatory protein that helps offsets negative health effects.

Now you know, make sure you train enough for your race.

References

Gill SK, Hankey J, Wright A et al (2015). The Impact Of A 24-h Ultra-marathon On Circulatory Endotoxin And Cytokine Profile. Int J Sports Med. 36(8): 688-695. DOI: 10.1055/s-0034-1398535.

Gill SK, Texeira A, Rama L et al (2015). Circulatory Endotoxin Concentration And Cytokine Profile In Response to Exertional-heat Stress During A Multi-stage Untra-marathon Competition. Exerc Immunol Rev. 21:114-128.