Sunday, July 28, 2019

How To Beat Muscle Cramps? Sunday Times Article

Sunday Times article 280719
Today's Sunday Times article on training for the Straits Times run says avoid muscle cramps by consuming more sodium? Nah, not totally true. Not at all actually. I've written about this exact same topic way back in 2015.

In that post, I wrote about how renown sports scientist Tim Noakes found no significant differences in sodium and magnesium levels in 72 ultra marathoners among those who cramped and those who did not cramp (Schwellnus et al, 2004). They found that sweating too much had no real effect on muscle cramps.

Try to think of when you last had a muscle cramp? After running 30 km in your marathon or after 3 km in a 10 km race?

Muscular fatigue (or when your muscles get too tired) is what really causes muscle cramps. The muscle cramps so you can avoid injury before you can push yourself further. That the Sunday Times article definitely got correct.  

Muscle cramping occurs mostly during races than during training. If you started your race too fast or you pushed too hard, that may cause your muscle to fatigue and then cramp. Other studies have shown that tough, hilly courses and poor pacing are predictive of muscle cramps.

I also wrote that sports drinks cannot replace your sodium levels during exercise. Your electrolyte levels actually rise when you sweat a lot. Yes, you read correctly. I'll explain this below.

Assume you have five cups of water and five teaspoons of salt/ electrolytes in your body. Say you sweat 2 cups of water and a teaspoon of salt/ electrolytes when you exercise, the concentration of salt/ electrolytes is now higher. It will remain higher as you become more dehydrated.

Apply this concept to our running physiology. Our sodium (salt) concentration 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. Even for a "salty sweater" (those who lose more salt than others when they sweat), they lose about 1.1 grams of salt max in every litre of sweat.

Hence, the theory that muscle cramping is caused by low electrolytes/ salt as a result of sweating is not true. You will definitely lose more water than sodium when you sweat. You can read more of that here.

You read it here first. Now you definitely know.

References



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.

Schwellnus MP, Nichol J, Laubscher T 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.

*The Sunday Times article is on page A27 under the Sports section. Go take a look.

Thursday, July 25, 2019

Playing More Sports Beneficial For Young Children - Straits Times Forum Page


ST 250719

I have written previously that you should not push young athletes to specialize in a single sport too early. It was a very popular article on our blog with many readers asking to share it.

In the article in the forum page today of the Straits Times, scientific studies suggest that children who play multiple sports between six and twelve are much better off. They develop stronger motor control skills, aerobic fitness and confidence.

Children who specialize in a single sport before twelve are more prone to overuse injuries and burnout.

I see many cases like this when the child is trying to get to a school of their choice via the Direct School Admission scheme which allows students to gain direct entry to a secondary school or junior college based on their sporting talents. Children in the Singapore Sports School are particularly prone.

Late specialisation sports includes track and field, badminton, football and basketball. So those of you who have children in these sports please remember not to push them. You can definitely support wholeheartedly them if they are interested.

You read it here first. Have a look the at Straits Time article if you're keen in the Forum section on page B8.

Wednesday, July 24, 2019

Another Way To Improve Your Running Economy

Small, quick steps
I wrote a few days ago about how to improve your running (or cycling) economy by inhaling carbon monoxide. Despite it being easier than training at altitude (and legal) compared to injecting yourself with illegal drugs, it can go terribly wrong if it's not done in a laboratory.

Well, I just read another article about improving your running economy, and it's a much easier way compared to the last article.

The researchers investigated whether a short training program of running 15 minutes for 10 days to increase cadence (or step frequency) to 180 steps per minute (90 strides / minute) will improve running economy.

The subjects were divided into two groups and they did training at the laboratory for 12 consecutive days. Running economy tests were done on day 1 and 12, followed by a maximal oxygen uptake test (day 1 only).

One group of runners completed a 10-day training program to increase cadence (or step frequency) on days 2-11. This consisted of running 180 steps per minute for 15 minutes at a self selected pace.

The control group completed the same runs without the step frequency training.

Oxygen consumption was significantly lower  for the group that did the cadence training but not the control group. The cadence training runners also had a faster cadence (7%) subsequently as well as a shorter step length (3.7%). Hear rates were 5.1% lower as well.

Seems like a much safer way to improve running economy to me than trying to inhale carbon monoxide from your car if you can't do it in a laboratory.

In the same way, cyclists can similarly improve by using a smaller gear to achieve a high pedaling rate.

As with all things pertaining with new training, do allow for time for your body to adapt to the new technique.


Reference

Quin TJ, Dempsey S et al (2019). Step Frequency Training Improves Running Economy In Well-Trained Female Runners. J Strength Cond. DOI: 10.1519/JSC.0000000000003206.

Saturday, July 20, 2019

Here's How To Improve Your Running Economy

Inhaling carbon monoxide?
I've been watching the Tour de France the last few days, especially the climbing stages and of course memories of previous doping cases come to mind. Erythropoeitin (EPO) was the drug of choice then and blood doping subsequently after a reliable test was developed to test for EPO.

So I was pretty shocked to say the least when I read about how you can possibly increase your haemoglobin (Hb) levels without taking EPO and without training at altitude.

Researchers in the following study got subjects to inhale carbon monoxide (CO)! Yes, you read correctly, inhaling carbon monoxide followed by running on a treadmill.

Twelve soccer players were recruited for their study. They were all non smokers, living at low altitude and had never trained at altitude previously. Their running economy, VO2 max and total haemoglobin (tHB) levels were measured before and after the 4-week training program.

They were randomly assigned to two groups. One group inhaled CO (1mL/kg body weight for 2 min) before all training sessions and a control group that didn't inhale CO before training. Both groups participated in a 4-week treadmill running program five times weekly.

I would not be writing this article if the results were not desirable. EPO hormone levels in the group that inhaled CO before training increased from 1.9 to 2.7 mIU/mL four hours later. After the 4-week training period, tHB, and VO2 max levels improved significantly by 3.7 and 2.7 percent respectively while there were no significant differences in the other group.

The researchers concluded that there was a sharp increase in the EPO hormone after inhaling CO, especially four hours later (that's very fast). The 4-week treadmill running program also improved total haemoglobin levels, VO2 max and running economy thereby suggesting that moderate CO inhalation could possibly be a quicker, cheaper, less dangerous and more convenient way to improve endurance performance in athletes.

Now I know what you're thinking (like my posed picture above). It could all go terribly wrong if you're not careful!


Reference

J Wang, Y Ji et al (2019). A New Method To improve Running Economy And Maximal Aerobic Power In Athletes: Endurance Training With Periodic Carbon Monoxide Inhalation. Front. Physio. DOI: 10.3389/fphys.2019.00701.

You can read the full article here.

Sunday, July 14, 2019

Is Your Favorite Healthy Food As Healthy As You Think?

Cereals galore at any supernarket
Since my accident, unless we're travelling, I always have the same oats for breakfast with Oatly oat milk. (Disclaimer- we are not sponsored by Oatly, we buy all the Oatly milk we drink). Sometimes I have them for lunch too.

My breakfast (left) and lunch
One of my patients who moved to the UK recently but came back for a meeting came to see me in the clinic commented that she has seen me eat the same oats in a jar five years ago. Some (good) things never change. Often, patients who see me eating my jar of oats (for lunch) often ask me what I'm eating.
My lunch jar that I eat at work
Thanks to my wife, we have definitely become lots more aware of what we eat as a family. We know nutrient dense food is good for us so we always try to eat and drink healthy.

The oats/ cereal we eat is nothing like the boxes of cereal you get the at supermarkets. It's common to see words like "wholesome', "all natural" on boxes of cereal there. Turns out they may just be claims.

A group of researchers analyzed more than 600 boxes of breakfast cereals across four separate studies. Their goal was to determine whether cereal products marketing claim like "no additives" or "high in vitamins" were supported by actual health benefits like weight loss.

Turns out, there was no substance to the claims. There was no link to the cereal's nutritional quality. This however, did not stop shoppers from buying cereals that were perceived to be "healthier".

More specifically, shoppers had a more positive attitude and chose products that were claimed to be made with healthy ingredients like whole grains over cereals that claim to remove something "bad" like gluten.

Shoppers also believed that "homemade" labels or cereal made with "no preservatives" tended to be more delicious. They also believed that cereals labelled as "low fat", "low sugar" or "light" helped them lose weight.

Next time you see such claims or boasts, remember these claims are not indicators of health benefits. Best to look at the ingredients to gauge sugar, fiber, trans fat and protein etc to help you decide.

Reference

Andre Q, Chandon P et al (2019). Healthy Through Presence Or Absence, Nature Or Science? : A Framework Understanding Front-Of-Package Food Claims. J Pub Policy Mtkg. DOI: 10.1177/0743915618824332.

My boys like Nutri Grain or Iron man food (as they call it) by Kellogg's. I do too, but it's got way to much sugar in it. I used to eat lots of it while in Australia.