How much food should I eat before a physical test?

        When I was an instructor for the Army I taught a multitude of classes. My favorite class to teach was physical fitness (shocker that a guy who writes a fitness blog likes to teach about fitness). It was one of those classes where I would just have a conversation with the students. No slides, no PowerPoints, just conversation. It was one of those classes I looked forward to facilitating.

 I start with one question,

 "How do you prepare for the ACFT?"

    As you can imagine the conversation would go in several directions, getting enough rest, Valsalva maneuver during the deadlift, little tricks for the Sprint drag carry like cutting down on the transitions between events during the sprint drag carry. One of the topics that would come up is food. I would go into foods that prevent GI issues. Eating more carb centric then protein centric foods. How caffeine (in small amounts) can be beneficial, how much water to drink beforehand to prevent bathroom usage during events. One topic that would surely come up is how much food to eat beforehand. Our ACFT's vary in time frame. During the spring/summer/fall it is typically at 0600 or 6am for your non-24-hour time people. During the late fall and winter, we would shoot for 1300 or 1pm to maximize the hottest part of the day. Depending on the class I would give different recommendations. The book answer is:

Less than an hour before the event=.5 gram of carbs per kilogram of body weight

2 hours before=1g of carbs per kilogram of body weight

4 or more hours=1-4g of carbs per kilogram of body weight. 

    If we were testing in the morning, we would recommend buying something the night before and having it prepared in the morning. Waking up at 4am to eat before a test isn't always the best since you are cutting into your rest. On the other hand, not eating enough leaves you without fuel before the test is over. This food balance is key to a successful test. 

    For example, a 190-pound individual is approximately 86kg. a half gram of carbs for 86kg is roughly 42 grams of carbs. That would typically be a medium banana and an 8oz Gatorade. For some crazy reason a person does want to get up early then that would entail eating 86 grams of carbs. A sample meal would be a medium bagel with jelly and a Gatorade. If the test is in the afternoon, then eating normal meals with snacks will get to the 1-4g per kilogram recommendations. 2.5g (roughly in the middle of recommended amount) would be 215g of carbs before the test. 215g of carbs is simply ensuring eating carb rich foods during breakfast, snack and a lighter lunch.

    One sure fire way to determine how much food to eat is to practice the nutrition strategies beforehand. Set up a day where you simulate the test then try different nutrient strategies. Make it a hard training day to replicate the physical demands of the test. Foods to avoid are foods that are higher in fat and fiber to prevent GI issues during the test. Normally fiber is under consumed but there is nothing worse than going to work out then having to run to the bathroom beforehand. Nutrition is individualized. Meaning it is something you have to try out before hand and tinker with your diet to ensure you're at peak performance.