Intermittent Fasting: A New Pattern of Eating or Just Another Diet?

Weight management, especially as we age, seems to become harder, even for athletes, which makes dieting more attractive. But for swimmers and other athletes, maintaining a healthy approach to food is critical because food restriction can impact performance and eliminating foods from a certain group can lead to nutrient deficits.

One of the “new” diets is intermittent fasting. While many versions of fasting have been used, Cell Metabolism published interesting research in June 2018 on men who have prediabetes who are showing beneficial effects on their blood sugar levels and blood pressure after following this approach to eating. Intermittent fasting also doesn’t involve calorie-counting or restricting any type of foods.

Very simply, instead of eating throughout the day and evening, as many people do, the idea is to restrict eating to a six-hour window, with the last meal occurring around 2 p.m., well before the end of the day. No evening meal or snacks are allowed. There are no restrictions on what or how much is eaten during the eating window. The fasting occurs during the remaining 18 hours of the day.

Why is this type of dieting getting attention? Quite simply, it seems to help blood sugar and insulin sensitivity, even though it may or may not produce weight loss.

There are several theories why the approach seems to help with prediabetes. Some indications, according to a study published in the Annual Review of Nutrition in August 2017, are that eating from morning to mid-afternoon syncs better with circadian rhythms and hormone levels. And while the intermittent fasting is not calorie-controlled, some people will consume fewer calories simply by skipping evening snacks.

But should athletes, and swimmers in particular, consider trying intermittent fasting? The answer depends on the following:

1. Are you training less than seven to eight hours per week?
2. Do you have a medical condition that warrants a fairly drastic approach to eating (e.g., prediabetes)?
3. Can you hold yourself accountable to not eat all afternoon and evening?
4. Are you prepared to stick with this type of eating approach for the foreseeable future? If not, the weight will simply come back and often you will regain more than you lost.
5. Will this type of diet work in the context of your life? For example, this type of eating approach would involve not going out to dinner or even eating an evening meal with your family.
6. Are the potential gains you might have from blood sugar control or weight loss worth the sacrifice and effort of making this type of dietary pattern change?

If you answered “yes” to all of the questions above, I’d encourage you to work with your doctor or a registered dietitian nutritionist and give it a go. If you answered “no” to any of the questions, I recommend you find another approach to changing your patterns of eating. And for athletes who train more than one hour per day, fasting will definitely impact your ability to train hard.

The bottom line: Dieting is very rarely successful for long-term weight loss, unless the changes that led to the weight loss are also permanent. The adverse changes to metabolism that occur with calorie restriction often lead a higher body weight once calorie restriction ends. So, while a healthy weight is important, rather than limiting calories, you should perform the following fixes to your lifestyle:

• Get enough sleep
• Manage stress
• Eat more fiber (whole grains, legumes, vegetables, fruit)
• Eat only when hungry rather than bored
• Manage overly large portions served by others (i.e., restaurants)

Nutrition is not rocket science, but it’s harder for many than a difficult workout or long main set. But since weight is predominantly controlled by the amount of food that we eat, rather than the calories we swim off, it’s very important to understand not only what you eat but why. Solving that issue is truly the key to better weight management.