You sweat through this workout every week. But this particular Tuesday? You're struggling way more than usual — moving slower, taking longer breaks, cutting sets short.

When you're not feeling a workout, not forcing yourself beyond what you can physically handle is an important part of preventing injury. But, it's frustrating when you end your workout feeling like you didn't accomplish much.

"We all want the time and effort we invest into a workout to feel like it's worth it. Having a bad workout happens, but if it's happening more often than usual, it might be time to take a look at a few of your lifestyle behaviors — specifically, the ones that affect your workouts the most," says Kim Lowry, sports dietitian at Houston Methodist.

Lowry says the main behaviors that can impact your performance during a workout are:

• What you eat
• How you recover
• How much sleep you're getting
  
  

With that in mind, here are four mistakes you may be making if you just struggled through a workout feeling low energy.

You're not eating the right foods at the right time

When we typically talk about diet and exercise, we often think about calories in versus calories out. But, aside from weight maintenance (or loss), what you eat plays a huge role in your performance during exercise.

"Your body and brain need energy during a workout. If you're well-fueled, there's energy readily available in your blood stream. If you're not well-fueled, your body is going to need to tap into your energy stores, which takes time," says Lowry. "This may result in feeling like you can't push yourself as hard as you usually can."

So, how can you make sure you start a workout with plenty of readily available energy? That comes down to when you eat and what you eat.

"One of the easiest mistakes to make is getting the timing of your meals wrong and going into your workout "fasted," making it both physically and mentally harder," warns Lowry.

Ideally, Lowry says you want to eat a well-balanced meal about three to four hours prior to working out. A well-balanced meal includes:

• Complex carbs, such as oatmeal, quinoa or sweet potatoes
• Colorful veggies, such as bell peppers, carrots or tomatoes
• Lean protein, such as chicken, plain yogurt or eggs
  
  

"If you're going to be exercising at a high intensity for longer than 30 minutes, I also recommend topping off your energy stores about an hour before your workout by eating some simple carbs, like a piece of fruit or granola," Lowry adds.

You're eating the wrong foods at the wrong time

The other mistake that's easy to make is eating the wrong thing too soon before your workout.

"While a piece of fruit is mostly made of simple carbs that your body can quickly digest to provide a pool of ready-to-use energy, foods that are high in fats and complex carbs or fiber take a while for your body to digest," warns Lowry. "Digesting food takes energy. So if you eat these foods too close to your workout, some of the energy that could've been dedicated to your workout is now being used to digest your food."

It can take up to an hour or two to digest fats and heavy carbs, so you'll also want to avoid eating these types of foods immediately before your workout.

You're not fully recovering between workouts

Exercise is a stress on your body. This short-term stress is good, though. It's what makes you stronger. But, your body also needs to recover after exercise, particularly when it's intense or frequent.

"After a workout, your body is recovering for up to 24 hours later. In this time frame, there are things you should do to make sure your body and muscles have the best chance of fully recovering before your next workout," Lowry explains. "If you aren't recovering fully, you're less likely to get the most out of your muscles — making your workout feel harder and affecting your progress."

Recovering between workouts has four key components:

• Loosening your muscles
• Rebuilding and repairing your muscle
• Reducing inflammation
• Resting
  
  

To prevent muscle tightness after a workout, Lowry recommends stretching, foam rolling, doing yoga or taking an Epsom salt bath.

"To rebuild your muscle, we look back to your diet. After a workout, eating foods high in protein helps promote the muscle protein synthesis needed to build and repair your muscles," explains Lowry. "The best time to refuel is within the first hour after your workout, since the blood flow redirected to your muscles during your workout makes them primed to receive nutrients. However, continuing to take in protein for the entire 24 hours your body is recovering is important, too."

Right after your workout, aim to get 20 to 40 grams of protein — ideally protein that's high in leucine, such as chicken, whey or soybean-based foods. If your workout included cardio, you may also want to refuel with 40 to 80 grams of carbohydrates, as well.

"One thing to keep in mind is that overloading your body with protein, 60 grams or more at one time, doesn't have added benefit towards muscle protein synthesis. Instead, continuously supplying your body with 20 to 30 grams of protein at every meal is a better strategy," adds Lowry.

The next piece of recovery after exercise, especially if your workout was intense or your workouts are frequent, is preventing exercise from causing chronic stress on your body.

"A great way to do this is to eat fruits, veggies and spices that contain antioxidants and phytochemicals, which help promote recovery by reducing the inflammation that occurs as a result of exercise," explains Lowry. "These foods include colorful veggies, spices such as a turmeric and ginger, and fruits like tart cherries."

Lastly, recovery takes time — and during this time, your muscles needs rest.

"Rest doesn't mean you can't be active. For instance, you still want to be moving around, stretching and walking," adds Lowry. "If you work out every day (or most days), a good way to fully rest your muscles between workouts is to periodize your workouts. This means working different muscle groups on different days, and switching between cardio, strength training and high-intensity workouts."

You're not getting enough sleep

Speaking of rest, we don't just mean rest from working your muscles — we mean rest for your whole body.

"Most of your muscle recovery happens while you're sleeping, since this is when your body release the most growth hormone. During this time, your muscles are repairing and rebuilding," explains Lowry.

Given this, and the fact that muscle recovery is important for getting through your next workout strong, it's easy to see why getting plenty of sleep can help improve your exercise performance.

Between workouts, Lowry recommends making sure you're getting seven to nine hours of sleep at night.

"If you're only getting four to five hours of sleep, you're not giving your body enough time to fully recover," adds Lowry.

Next Steps:

• If your workout performance is suffering or you’re experiencing pain during or between workouts, learn how our sports medicine experts can help you get moving and stay moving.