Any serious athlete will tell you that proper nutrition is the key to unlocking the potential of your training program. No matter how much weight you throw around, hypertrophy will not come if you’re not in a caloric surplus. Likewise, all the cardio in the world will not help you shed any fat if you’re eating too much. But these aspects of nutrition are not controversial.
However, there is a substantial amount of mythology and misinformation circulating in the fitness world regarding nutrition.
One particularly popular point of contention is meal timing. Even the least-experienced fitness enthusiasts have probably heard the theory that eating prior to sleep is essentially a guarantee of fat gain, as the calories consumed close to the end of the day won’t be used. But this isn’t quite accurate. While sleeping does not burn many calories – only about 61 per hour – this isn’t too much different than the amount burned when sitting around – 68 – as one might do at school or work (1). And yet no one thinks twice about eating before work.
It’s important to remember that your metabolism doesn’t sleep, even when you do.
Several studies have focused on meal timing, and yet none of them found that eating during the evening led to unreasonable fat gain. One particularly interesting study suggested that eating at night might be beneficial; this research found that subjects consuming 70% of their daily caloric allowance had “better maintenance of fat-free mass” than those consuming most of their calories earlier in the day (2).
In the long run, it seems that the total number of calories consumed, not when they are consumed, is the determining factor on body composition.
One research review compiling the data from a number of studies concerning dieters concluded that “meal pattern has no significant impact on weight loss.” Additionally, the review found that 24-hour energy expenditure was not significantly altered when varying patterns of “gorging” and “nibbling” during the morning and evening (3). According to the observations, energy expenditure seemed to shift based upon the timing of caloric intake.
What else we know
A more valid argument against consuming a lot of calories late in the day holds that such a pattern might deprive the body of proper nutrients around training, when they are needed for recovery and growth. While it is undoubtedly essential to make sure you have the proper fuel to get through your workout, clustering significant caloric intake and protein consumption around exercise does not seem to be as imperative. A 10-week study investigated the effects of supplementing protein in the morning and evening versus immediately before and after weight training. While these great variations in timing might seem to have the potential to wreak havoc on recovery, muscle building and strength, this was not the case. The study found no significant variations between the groups, and researchers concluded timing of protein supplementation “does not provide any added benefit to strength, power, or body-composition changes”.
From these studies, it would seem that regardless of timing, overall caloric balance should be your primary concern. So don’t worry – unless you’re pushing yourself into an unwanted caloric surplus, that after-dinner snack going to kill you.
1. Activity Calculator; About.com: http://caloriecount.about.com/activities-inactivity-ac7
2. Keim, Nancy L., et al. Weight Loss is Greater with Consumption of Large Morning Meals and Fat-Free Mass Is Preserved with Large Evening Meals in Women on a Controlled Weight Reduction Regimen. The Journal of Nutrition, 1997; 127(1): 75-82
3. Bellisle, F., et al. Meal Frequency and Energy Balance. The British Journal of Nutrition, 1997; 77(1): 57-70
4. Hoffman, Jay R., et al. Effect of Protein-Supplement Timing on Strength, Power, and Body-Composition Changes in Resistance-Trained Men. International Journal of Sport Nutrition & Exercise Metabolism, 2009; 19(2)L 172-186