Is Drinking Milk Or Eating Beef Better For Recovery After Exercise?

Picture by Steve p2008 from Flickr

After your workout, is drinking milk better or eating beef better for recovery? Make a quick guess before you read on.

That was the basic question the authors wanted to find out. The impact of beef and milk as a protein source as a post workout meal.

Here's what made this study unique and interesting.The researchers injected a cow with amino acids specially labelled with a rare isotope of carbon. After that they milked the cow and had it slaughtered to produce meat. The researchers then used the specially labelled milk and meat to feed the subjects in their trial.

This allowed the researchers to track where the protein went through muscle biopsies after the subjects did a strength training session.

The subjects consume 30 grams of protein from either 350 ml of skim milk or 158 grams of ground beef. Rate of protein synthesis (how quickly your body is building new muscle) were as follows.

Picture from Am J of Clinical Nutrition

Milk clearly has the edge two hours after working out. However, after five hours, the rates of protein synthesis were similar.

Other than using the same cow for both milk and beef, this study differs from previous studies as soy protein or whey powder is commonly used in other studies.

The researchers suggested that there may be larger differences between milk and meat if the amount of protein consumed were smaller. 

Personally I would like to know if other kinds of protein such as eggs, chicken or other vegetable proteins will produce different results.

References

Burd NA, Hamer HM et al (2013). Substiatial Differences Between Organ And Muscle Specific Tracer Incorporation Rates In A Lactating Dairy Cow. Plos One. DOI:10.1371/journal.pone.0068109.

Burd NA, Gorissen SH et al (2015). Differences In Postprandial Protein Handling After Beef Compared With Milk Ingestion During Postexercise Recovery: A Randomized Controlled Trial. Am J Clin Nutr. 102(4) 828-836. DOI: 10.3945/ajcn.114.103184.

Carbohydrates Still The Best Energy Source For Racing

Picture by Erik Stattin from Flick.

Stick to your carbohydrate diet if you want to race well? Or train your body to burn more fat to be more effective in sustaining your effort. Much has been debated over how much carbohydrates and fat we need in our diet to enhance running (or endurance) performance.

Since our bodies can only hold limited amounts of muscle glycogen (or carbohydrates), we usually "hit the wall" after about 20 miles of running. Our bodies store large amounts of fat and if we can utilize the fat stores, we can potentially rely less on carbs.

And fat-adapted running diet is getting popular, especially in the long/ ultra distance running community in an attempt to teach their bodies to use fat (instead of carbs) for fuel.

Prominent exercise physiologist Tim Noakes has suggested that training your body to burn more fat is a more effective way to sustain effort (especially in a long race). Noakes may be right about utilizing fat for ultra distances and we await more research from him.

But carbs may be better if you are running high intensity intervals or racing hard and fast, so says a recently published research.

The researchers studied a group of male competitive runners in four randomized trials running on a treadmill at a speed of 95 per cent of their best half marathon time to exhaustion.

The runners consumed a pre run meal before each trial with different nutritional values. Runners in the first two trials were fed carbs in the form of a jelly. Runners in the next two trials fasted overnight and were given a jelly that looked and tasted the same to the carb group but contained no calories.

Runners in trials two and four were given nicotinic acid which prevented the use of fat stores during testing. This is to test whether blocking the use of fat as a fuel hampered run performance.

Results showed that majority of the time, (83-91 per cent) carbohydrates were the source of primary fuel. The nicotinic acid did not affect the runner's performance or the body's ability to use carbohydrates as fuel. The runners did use a small amount of fat as fuel, but the main source was still carbohydrates.

Your friends or other runners may want to experiment with utilizing more fat to fuel their runs, but this study shows that at least for races up to half marathon, carbohydrates are still best for getting you to the finish line or clocking your personal best timing.


Reference

Lackey JJ, Burke LM et al (2015). Altering Fatty Acid Availability Does Not Impair Prolonged, Continous Running to Fatigue: Evidence For Carbohydrate Dependence. J App Physiol. DOI:10.1152/japplphysiol.00855.2015.

**Note from a runner

A friend who's been on a low carb,  high fat Paleo diet shared that adding carbs back to his diet can be discouraging. For every ounce of carbohydrate he ate after training his body to be used to low carbs, his body stored three ounces of water. His weight shot up quickly.

You Should Not Be Heel Striking

Picture by richseow from Flickr

In the picture above, you can see clearly the lead runner and a few others behind him heel striking whilst running. So is heel striking bad?

A group of Danish researchers studied runners who landed on their heels while running, The runners had a personal best time of 17 minutes or slower for 5 km.

In the study, the runners ran 1 km on a track with a force plate at three different speeds. 8 km/ hour (about 12 min/ mile), 11.79 km/ hour (8:20 pace) and 15.78 km/ hour (slightly over 6:00 pace).

The results showed that the total load on the front of the knee actually increases with slower running. This can cause or aggravate anterior (or front) knee pain, also commonly known as runner's knee.

Although the load on the runners' knees was higher on each stride during faster running, the runners took more strides to cover the same distance if they ran slower. As a result, the runners accumulated 80 per cent more load on the front of their knees when they ran at a slower pace.

The results explain why running more mileage (and heel striking) is linked to pain at the front of the knees. This also explains why runners with knee pain who switched to running with minimalist type shoes with the correct technique stopped having knee pain. Note that it has to be correct technique, otherwise the impact can be 7 times greater.

The authors suggest that if you are a heel striker with knee pain you may want to consider running shorter distances at a faster pace to limit the cumulative loads on your knees.

Well, better not heel strike when you run to avoid getting knee pain in the first place.

Reference

Petersen J, Sorensen H et al (2015). Cumulative Loads Increase At The Knee Joint With Slow-speed Running Compared to Faster Running: A Biomechanical Study. J Orth Sports Phy Ther. 45(4): 316-322. DOI: 10. 2519/jospt.2015.5469.

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.

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.

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.

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.

Notice 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.

Adjustable length for the ear pieces

Lens clarity looks superb while trying it so far, I'll find out while riding tomorrow.