1. When you WILL work out.
While this may seem obvious, you should not lose sight of the fact that exercise is almost always preferable to no exercise. While technical “nit-picking” can help make your fitness journey easier, it can also work against you if you get too wrapped up in it. Exercise and healthy eating will always trump all other advice. There is every excuse in the book, including “I missed my optimal window for training so I skipped today’s workout.” Don’t let this happen. Unless you’re injured, sick, or overtrained, exercising is better than not exercising. Schedule your workout when you have the best chance of getting it done.
2. When you FEEL the best.
There are times during the day when you will have a slight physiological advantage if you work out during them, but none of those trump the psychological edge you have if you feel like exercising. As simple as this sounds, effort equals results more than any other one factor. This means that if you’re a night owl, work out at night. Morning person? Work out first thing in the morning…you get my drift. Any time you’re in the mood to really Bring It will work because, by far, the biggest physiological changes happen to your body when you push yourself further than you’ve pushed yourself before. There’s a reason the Beachbody P90X mantra is “Bring It.” The closer you get to putting in 100% effort, the more you force your body into an adaptive state, which is exactly where it needs to be in order to change.
3. When your glycogen stores are full.
Now, let’s get technical. Your body can push itself anaerobically longer and harder if you begin your workout with a full tank of muscle glycogen. This will let you lift more weight, jump higher, move faster—pretty much improve every important aspect of every workout that’s not tied to recovery or aerobic efficiency.
Glycogen is mainly recharged by carbohydrates, and is extinguished very quickly with exercise, brain activity, and most other tasks. This means it fluctuates throughout the day and is always highest immediately after you digest a meal containing carbohydrates. This means—depending on your eating schedule—your body is probably primed for peak exercise in the late morning, afternoon, or early evening.
At night, your body can store glycogen, meaning that it’s possible to wake up and train in the morning before you’ve eaten and still have enough energy to get through a workout, but this is a theoretical scenario. Most of us, especially when we’re training hard and not eating a ton, will burn through glycogen recovering from the prior day’s activities. The result is that those early morning workouts can lead to something called “the bonk,” which is what happens when your body runs out of glycogen. Essentially you lose the ability to push your anaerobic realm, and you feel like you’ve hit a wall.
Bonking is not one of those “good pain” times. When your body is out of glycogen, it starts to break down muscle tissue and you quickly begin to offset the fitness gains you’ve made. It’s inevitable that it will happen to you at some point. When it does, don’t try and push though. Instead cut your losses and get on the recovery program by eating, resting, and then reevaluating your eating schedule and/or choice of workout times.
If exercising when your glycogen stores are low is the only time of day available, you can fix the situation nutritionally. If it’s first thing in the morning, eat a half or a whole banana or drink a half or a full serving of Results and Recovery Formula (depending on how long you’re training) before you start your workout. If that helps, try adding another serving of complex carbohydrates to your evening meal and then skip the banana. If that doesn’t work (you’ll know if it doesn’t—bonking isn’t subtle) it means you’re on a nutritional edge and aren’t eating enough calories to recover from your workout program. It’s time to reevaluate your daily caloric intake.
4. In the morning on an empty stomach.
In the morning, before you’ve eaten, your body is forced to utilize its fat stores for energy, and you can train your body to be efficient at doing so, which is cool. You’re also “burning fat,” which sounds even cooler (although it’s not nearly as effective as “burning glycogen” when it comes to losing body fat). While fantastic, in theory, it’s not if you force your body into a situation where you bonk.
You won’t bonk, however, unless you’re training anaerobically (in other words, hard—as in your heart rate is pegged during parts of the workout). This means easy workouts can have added benefits if done in the morning on an empty stomach. This is why during programs like P90X Doubles, the easier workout of the day is scheduled in the morning.
5. At night before bed.
This time of day is last for a reason. Unless it is really the only time you will work out or the only time you feel the best, you should probably avoid it.
Working out directly before bed can affect your sleep. Most people have a hard time getting to sleep after a workout because exercise can throw off your melatonin, the hormone that regulates sleep, among other things. This isn’t ideal because sleep is very important for recovery. It’s when your body naturally produces most of its own performance-enhancing drugs in the form of hormones. Anything that hurts your ability to sleep should be eliminated if possible.
Exercise also utilizes a lot of nutrients, which are further depleted at night. If you’re on a strict diet, perhaps trying to lose weight, you run further risk by training and then not eating to recover from the workout prior to bed. If you’re on a low-calorie diet and plan to train hard at night, you should follow your workout with, at least, a nutritional recovery strategy (Beachbody Results and Recovery Formula), if not a small meal before going to sleep.
If your sleep is not impacted by your workout, there’s nothing wrong with training at night. Just follow nutritional protocols that don’t leave you depleted and starving when you wake up. This can be so severe that you wake up in the middle of the night, a common issue with bodybuilders and fitness trainers getting ready for competition. This is not ideal as it means your body is essentially bonking during sleep. And while that’s okay if your goal is to pose in front of a crowd with absurdly low body fat, like a bodybuilder, it’s also a sign of starvation and, if done too long, will cause your body to begin to shut down its metabolic processes.
The bottom line is that everyone’s body responds differently. We all need to exercise and most of us can eat better. In between are a lot of individual variables. When it comes to getting your best possible workout, psychology often trumps physiology. Exercise when you can and pay close attention to your performance. Then choose your preferred workout time based on your results. It’s really that simple.