Improve your body composition
Intermittent fasting is known for its weight loss benefits. This can be really important in cycling. A 2020 trial found that elite cyclists following the 16/8 protocol, where they are only allowed to eat inside an 8-hour window, lost weight and improved their body composition. This resulted in an improved peak power-to-weight ratio. Similar results were observed in a different study of 23 male elite runners following the 16/8 intermittent fasting protocol.
Both of the abovementioned studies showed that cyclists and runners were able to maintain their initial performance during the 4-week trial while losing weight. This is impressive because losing weight often comes at a cost of performance. There are also studies following athletes during Ramadan, a month when they fast from sun-up to sundown, which is a form of time-restricted eating. This research shows that athletes who manage to maintain training load, body composition, and sleep length and quality do not lose performance while fasting during Ramadan.
Train low, race high
Improving body composition while maintaining performance is a great benefit but what if you’re already close to your ideal weight? There is one more way to make use of intermittent fasting for improved performance. If you go beyond just the timing of your meals but also take into consideration their composition, you can use intermittent fasting to create a train-low and race-high situation.
Train low means that you are doing your training session without carbs. That means you either fasted before or ate foods low in carbohydrates and you also don’t consume any carbs on the bike. Training with low carbohydrate availability teaches the body to oxidize a higher proportion of fat for energy and it improves endurance adaptations. The problem is that you can only do low- to mid-intensity rides like this. You need carbs to fuel your high-intensity training and racing.
When you plan your intermittent fasting right, you can get the best of both worlds. You can do your low-intensity training session in the fasted window to boost endurance adaptations. And you can schedule your interval and speed training inside your feeding window for optimal carb intake. There have been several studies showing that this approach can lead to performance improvements but there are also others showing no benefits.
There is a lot that goes into peaking for a race and not every study designs their regimen like an athlete would pre-race. This is also a good reminder to keep expectations realistic. Even if a nutrition strategy is likely to give you a performance boost, it’s not a given you will notice it. The last article in the series will be all about tips to help you succeed if you decide to give intermittent fasting a try.