By Chris Carmichael, Founder and Head Coach of CTS
Eating in the evening often gets a bad rap because people associate it with mindless snacking and polishing off a whole bag of chips or a full pint of ice cream. Sometimes, though, what is bad for a sedentary population can be good for athletes. Concentrated sources of simple sugar aren’t recommended if you’re going to stay on the couch, but they’re great for the final hour of a race. Added sodium can be a major problem for sedentary people with hypertension, but it’s also a key component of sports drinks. Nighttime eating can indeed lead to overconsumption of calories and encourage poor food choices, but for athletes it may improve recovery, increase muscle protein synthesis overnight, and even help you get to sleep faster.
So, the question we often get is: Should athletes eat at night so they have fuel for recovery and muscle protein synthesis, or should they extend their overnight fast by ceasing food intake early in the evening? Here’s a look at how you can decide which route to take.
While endurance athletes and coaches often focus on efforts and strategies to avoid overeating, it is important to recognize that endurance athletes with high training volumes and workloads sometimes struggle to eat enough food to meet their daily energy needs. Nighttime feeding can be helpful by providing the opportunity to consume adequate calories without increasing the size of meals throughout the day. This is an important consideration because eating larger meals less frequently leads some athletes to feel too full, or like they are force-feeding themselves. Inserting an additional meal can be helpful for athletes who have elevated energy needs but prefer smaller or “normal” sized meals. Some add in a “second breakfast” (like Tolkien’s hobbits from “Lord of the Rings”) or expand a mid-afternoon snack to a more substantial meal. Once total daily energy intake is adequate, there may be good reason to reserve some of those calories for a pre-sleep feeding.
Pre-Sleep Protein Intake
Muscle protein synthesis will continue throughout the day and night, provided there are adequate amino acids available. The overnight fast represents the longest interval between feedings, and a 2016 study by Trommelen and Van Loon showed that pre-sleep ingestion of protein stimulated the rate of overnight muscle protein synthesis enough to exceed muscle protein breakdown during the same period (see figure below).
It is important to note, however, that the study was conducted in conjunction with resistance training and not endurance training, and the authors note, “It remains to be established if pre-sleep protein can augment the adaptive response to endurance-type exercise training with greater increases in skeletal muscle oxidative capacity, vascular density and/or endurance performance capacity.” Another important distinction is that pre-sleep protein was compared to a non-protein pre-sleep feeding, not to protein consumption on a different schedule.
Before you dismiss pre-sleep protein for endurance athletes, consider the bigger picture. Research has shown that endurance athletes benefit from 1.4-1.6 grams of protein per kilogram of bodyweight per day, and older endurance athletes benefit from intakes closer to 2 g/kg/d. For some 75-kilogram athletes, sourcing 120-150 grams of protein in a day can be a challenge. Standard sports nutrition guidelines also recommend spreading protein intake throughout the day in 20- to 40-gram portions rather than concentrating protein intake on one or two big meals. Additionally, research suggests that while 20 grams of protein may be sufficient to stimulate muscle protein synthesis after exercise, 30-40 grams may be optimal for nighttime feedings. (Snijders 2019) Pre-sleep protein is an opportunity to meet daily protein recommendations and enhance recovery by supporting overnight muscle protein synthesis.
Using nutrient timing to manipulate carbohydrate availability for workouts has become a very popular dietary strategy for athletes. The most common application is to restrict carbohydrate and/or total calories in the evening following a late-day, glycogen-depleting bout of exercise. The next morning, the athlete has the opportunity to start their next exercise bout with low carbohydrate availability. This strategy is more suitable in conjunction with lower-intensity aerobic endurance morning rides. High-intensity interval workouts are more effective when completed with high carbohydrate availability.
For athletes who are not attempting to start morning workouts with low carbohydrate availability may benefit from pre-sleep carbohydrate intake. In addition to augmenting total daily calorie needs mentioned above, and supplying the fuel for glycogen replenishment, eating some carbohydrate about an hour before bedtime may decrease sleep latency. By helping you get to sleep faster, carbohydrate provides an opportunity to increase sleep efficiency, which is the amount of time you are asleep relative to the amount of time you are in bed.
Does the type of carbohydrate in a pre-sleep feeding make a difference? Maybe, but in the bigger picture it appears that a long-term diet that is high in carbohydrate helps decrease sleep latency, and that high glycemic index foods (simple sugars) incorporated between 1-4 hours before bedtime can be additionally helpful. In contrast, it may be better to choose a low glycemic index carbohydrate source if you are having a bedtime snack within an hour before going to sleep. (Halson 2014)
Short and Simple Takeaway
While sweet and savory are not always analogous to high and low glycemic index foods, some athletes find it useful to think of this as: Sweet at sunset, savory at bedtime. This may help you put away the sugary foods earlier in the evening and turn toward protein and complex carbohydrates for pre-sleep feedings within an hour of bedtime.
References and Suggested Reading
Halson, Shona L. “Sleep in Elite Athletes and Nutritional Interventions to Enhance Sleep.” Sports Medicine, vol. 44, no. S1, 2014, pp. 13–23., doi:10.1007/s40279-014-0147-0.
Reis, Caio E.G., et al. “Effects of Pre-Sleep Protein Consumption on Muscle-Related Outcomes — A Systematic Review.” Journal of Science and Medicine in Sport, vol. 24, no. 2, 2021, pp. 177–182., doi:10.1016/j.jsams.2020.07.016.
Snijders, Tim, et al. “The Impact of Pre-Sleep Protein Ingestion on the Skeletal Muscle Adaptive Response to Exercise in Humans: An Update.” Frontiers in Nutrition, vol. 6, 2019, doi:10.3389/fnut.2019.00017.
Trommelen, Jorn, and Luc Van Loon. “Pre-Sleep Protein Ingestion to Improve the Skeletal Muscle Adaptive Response to Exercise Training.” Nutrients, vol. 8, no. 12, 2016, p. 763., doi:10.3390/nu8120763.