Michael Hull is a researcher at Examine.com, the research-based resource on supplementation and nutrition, and a CISSN-certified MS(c) at McGill University.
How important is peri-workout nutrition, really?
It’s dependent on your fitness goals and workout routine. Obviously, peri-workout nutrition will be less critical for the casual gym-goer than for an elite athlete. But there are a few other factors to consider:
- Workout duration
- Workout intensity
- Time between workouts
- Personal fitness goals/preferences
Peri-workout nutrition becomes more important in helping to sustain performance levels and recovery when workouts are longer, more intense, or when rest periods between workouts are short. Athletes will need to be more systematic in their approach to eating around workouts while those with more modest exercise routines can afford to be a bit more relaxed.
But what’s the best practice when it comes to fuelling mid-workout? Plenty of supplements claim to be essential, but there are only a few with evidence to back it up.
Is there any evidence for the benefits of taking BCAAs mid-workout?
There is some mixed evidence indicating BCAAs may help relieve cognitive fatigue during endurance or mixed-intensity exercise lasting two hours or more. The studies usually supplemented BCAAs pre-workout, so the effects of mid-workout supplementation aren’t so clear. Another caveat is that some trials indicated anti-fatigue effects may be more pronounced in novice exercisers. Overall, when looking for supplements to enhance exercise performance BCAAs would be low on the list — other supplements, such as creatine or caffeine, have far greater evidence for their efficacy.
What else works?
Mid-workout carbohydrate intake can help sustain performance levels. If performing short, moderate intensity exercise sessions of 45 minutes or less, mid-workout carbs are probably not necessary as the energy from a meal consumed in the previous two or so hours will likely sustain you.
Exercise lasting 45 minutes or more may benefit from some intra-workout carb intake. Endurance exercise and stop-and-start sports, which tend to last from 60 to 150+ minutes, are the most likely to benefit from mid-workout carbs.
These longer workouts can also increase hydration needs. So you can knock out two birds with one stone by drinking an exercise beverage that contains 6–8% carbohydrate (a lot less than most sports drinks) to optimize absorption, oxidation for energy production, and to minimize the risk of an upset stomach. For most other supplements, their benefits usually require you take them pre- or post-workout.
Ultimately, there’s little evidence that you need a carbohydrate supplement if your workout is 45 minutes or less. If you eat plenty of protein you’re probably getting enough BCAAs from your regular dietary intake, and BCAAs are unlikely to help. If you’re struggling with fatigue or doing fasted training, it’s worth experimenting to see what works – but you’d probably be better off getting your pre and post-workout nutrition on point, and concentrating on crushing your workout when you’re in the gym.