- Dr. Kaustubh Radkar
Intermittent fasting for the endurance athlete
Intermittent fasting is one of the latest nutrition trends, that is garnering a lot of attention of late. In the past few weeks, suddenly a lot of athletes are discussing this, some are even following it with varied results. With this small article I am giving you a small synopsis of my personal experience, and the theory behind it. We are not evening hitting the tip of the iceberg, so I believe this will be an ongoing series of write-ups as new research comes out with more insights on intermittent fasting.
Where did this come from?
Japanese scientist Dr. Yoshinori Oshsumi’s Noble winning work on autophagy is the prime reason intermittent fasting has gained ground. Autophagy is the natural process where the body cleanses itself of damaged, dead and unrepaired cells. Autophagy requires right conditions to take place, for which nutrient deprivation is the key activator. Without going into too much details, it requires 12-36 hours of full abstinence from food for autophagy to be activated; however, one must drink lots of water that is a key factor to achieve
How does exercise relate to autophagy?
A lot of research shows that like nutrient deprivation, exercise also stimulates autophagy. Sweating, and post workout soreness puts stress on the body, which allows the eating of damaged cells within body. Working out causes microtears in the body, which the body works hard to heal, making it stronger and increasing resistance power.
The two common methods of intermittent fasting?
While there are several different ways the most common fasting patterns are:
1)5:2 method where you reduce maximum calories to 500-600 for 2 days a week (doesn’t meet guideline for full abstinence). A huge con is you will not get enough nutrients to take you through the 2 days, if exercise sessions are planned on those days you will suffer from poor performance due to low caloric intake, and more importantly inadequate recovery nutrition.
2) 16:8 method where you eat for 8 hours and fast for 16. With this method, you may land up skipping breakfast, not a good idea with longer duration workouts (those lasting longer than 90 mins).
Okay, lets get to the point is intermittent fasting good or no?
There have been small size studies that have showed intermittent fasting has helped subjects in loosing body fat, reduced heart rate, and increased pain threshold. These are to be taken with a pinch of salt, as study size has been small, maximum period has been of 6 weeks (in all studies I looked at) or conducted on rodents.
Be mindful if you are considering intermittent fasting. Understand where in the season you are then decide if its worth the risk. If you are caloric deficient, it may have negative impact on training and, also open door to you falling sick due to reduced immunity. Under fueling may also result in increased chances of getting injured so that’s not a good position to be in.
If you are training for an important race and want to shed those few extra lbs, intermittent fasting may help early in the season when exercise intensity is low. If you are mid-season or getting close to race-day I feel this isn’t something to be experimented with.
Just like any “fad diet,” its always a question of sustainability, can you make this a lifestyle? And I think for most athletes the answer is NO.