The Pros and Cons of Intermittent Fasting

intermittent fastingIntermittent fasting has been a hot topic for discussion lately. Some people swear by it, others think it’s just a fad. Either way, there are some upsides and downsides to intermittent fasting. Let’s take a look and see how it can affect people who live an active life.

Two of the most popular patterns of fasting for athletes are the full day fast and the 16:8 fast. In the full day fast, you take a break from eating for a full 24 hours, usually once a week. In the 16:8 fast, you take a break from eating for 16 hours and then have an eight hour window to eat. Most people who do this type of intermittent fasting will partake 2-3 times per week.

The Pros of Intermittent Fasting

Although the studies have been small and are relatively new, there is research that shows a number of positive effects of intermittent fasting.

  1. Increases Human Growth Hormones (HGH): This hormone has to ability to speed muscle recovery, increase energy, build lean muscle mass, and improve athletic performance. People who fast have been shown to have higher levels of HGH.
  2. Reduces inflammation: Fasting has been shown to reduce oxidative stress and prevent chronic inflammation in the body, which is linked to many diseases and conditions.
  3. Enhances cognitive function: Studies have shown that when your body is in a fasting state, your concentration is improved. Your brain is able to laser focus on tasks at hand, meaning quicker reaction times, fewer errors, and ultimately improving performance.
  4. Effective weight loss: Intermittent fasting can decrease insulin resistance and increase metabolism. The full day fast is especially effective at weight reduction since it requires you to abstain from eating for a full 24 hour period, reducing your overall caloric intake.

Full Day Fasting

  • Good for those with weight class requirements
  • Beneficial for athletes that need to stay lean for optimal performance
  • Can be useful for endurance athletes (as long as you don’t fast on a training day)

16:8 Fasting

  • Ideal for athletes who benefit from enhanced focus and concentration
  • Useful for those who participate in weight training

The Cons of Intermittent Fasting

When you’re in the fasting state, there are a few issues that can arise. It’s also important to note that fasting is more beneficial to some groups of athletes than others. For example, a baseball player may find the increase in focus that fasting can provide to be very advantageous. Whereas, the endurance athlete may experience a decline in performance while fasting, since they rely on immediate energy provided by food to fuel their workouts.

  1. Decreases energy: It’s no surprise that giving up food for long periods of time can leave us feeling tired and weak. Many people report headaches, bad mood, and a lack of energy when they don’t follow their normal eating schedule. If you train heavily, the effects can be even worse. Your body is working hard but it doesn’t have the necessary supplies to fuel your efforts. For those who do train on fasting days, it’s recommended to supplement with BCAAs. However, even if you do supplement, your performance will most likely be lower on fasting days.
  2. Risks for women: Fasting is more likely to lead to nutritional deficiencies and issues with fertility and reproduction for women than for men. Although intermittent fasting has its benefits, the risks are greater for some women.
  3. Decline in performance: Many athletes (especially endurance athletes) need to be able to quickly tap into energy stores. However, if there is no immediate energy available, your body and mind will be negatively affected and performance will suffer.

Full Day Fasting

  • Not favorable for athletes who need to put and keep weight on

16:8 Fasting

  • Not ideal for endurance athletes
  • Not conducive for those who train a lot each day

Whether intermittent fasting is the right choice for you depends on your goals and health condition. Intermittent fasting is not for everyone, but if you do decide to try it for yourself, be sure to strategically incorporate fasting days with training to minimize the potential negative effects.