[ad_1]
Exercise long enough and everyone hits the same wall, but the human body still allows you to work hard now and rest later.
Athletes competing in endurance events, such as the Ironman triathlon or ultramarathons, regularly push their bodies beyond their limits.
These events are exhausting, but they take place on a single day.
Now imagine that you are organizing the Race Across the USA, a 3000 km run from California to Washington, DC – runners run six marathons a week for 20 weeks.
A new study found that when people maintain this level of effort for as long, they all reach the same metabolic limit.
The study was published June 5 in Science Advances.
At this point, their bodies can burn calories only 2.5 times their resting metabolic rate without having to break down their own tissues to get energy.
The researchers say this could mark the limit of the level of physical activity that people can maintain in the long run.
Brent Ruby, PhD, director of Montana for Labor Physiology and Exercise Metabolism at the University of Montana, who did not participate in the study, described the limit of energy expenditure as follows: "If every day for a year, what is the maximum energy expenditure that I can maintain without losing weight?
Ruby pointed out that this is not the upper limit of energy expenditure.
A study by Ruby and his colleagues found that Ironman athletes had a total energy expenditure of 9.4 times their resting metabolic rate. For athletes participating in a 100-mile ultramarathon, it was 8.5 times their resting metabolic rate.
The new document shows however that the energy expenditure that people can bear decreases with the duration of the event and is around 2.5 times the resting metabolic rate.
They suggest that this limit is determined by the ability of the digestive system to break down foods and absorb nutrients to fuel physical activity.
Peter Weyand, PhD, professor of applied physiology and biomechanics at Southern Methodist University in Dallas, who did not participate in the study, thinks this idea is "certainly plausible".
"In this scenario, getting calories in the blood through the intestines or intestines becomes of utmost importance," said Weyand.
He said that research in this area has led to experiments on how to speed up the calorie intake – in the form of simple carbohydrates – from the intestines to blood through the muscles. Several sports nutrition products are based on this.
The new study is focused on the amount of effort that people can endure over long periods of time such as 20 weeks or more without losing weight.
But athletes participating in shorter endurance events regularly burn more calories than they absorb – which creates an energy deficit.
In the Ruby study, athletes participating in the Ironman or Ultramarathon lost 2.5 kg and 1.5 kg of body weight, respectively. He said it was not so bad considering they burned about 9,000 and 16,000 calories during the race.
If athletes burn 9,000 calories or more during a race, they have no way of eating enough to keep up, but they can catch up after the race.
"Participation in a single Ironman or Ultramarathon will create a huge energetic crater," said Ruby. "But over the next few days, you just eat and eat everything you can find, and you get back to normal – very quickly."
Other factors can affect the level of effort that you can maintain. One gets rid of excess body heat.
The new study also looked at people competing in trekking in the Arctic – a cold environment.
Researchers found no difference in maximum energy expenditure for athletes competing in cold or warm weather.
They write in the newspaper that this may be due to the fact that endurance events do not usually take place under very high temperatures. If they were, not being able to get rid of body heat could affect performance and energy expenditure.
Ruby said that talking about energy expenditure without taking into account fluid needs does not give a complete picture.
In his study, athletes participating in the 100-mile ultramarathon lost 87% of their initial total body water.
"Watch it for a moment," said Ruby. "Consider losing and trying to replace as much fluid in less than 48 hours."
The Ironman and Ultramarathon athletes included in Ruby's study were all non-elite runners.
This shows that with the right training, good nutrition and mental stamina, many people can compete in these races.
"Each of us has the ability to do it," said Ruby.
Meghan Laws, ultramarathon coach, gave some tips for coaching an endurance event without "touching the wall":
- Do not force the training. If you're really struggling to get motivated, it's time to stop for more than a few days and focus on rest, relaxation and good nutrition.
- Alternate easy and difficult days. Think of the easy day as a reward for hard work.
- Avoid the FOMO trap. Instead of looking at social media to see how your friends are training, focus on yourself and what's best for you.
- Plan your training for the race. Try to optimize your training so that you get your best performance when pinning the race number.
[ad_2]
Source link