Should You Exercise When You’re Tired?

Should you exercise when your tired?

You’ve had a hard day at work, and all you want to do is plop down in a chair and relax, but you have a date with a set of weights! It’s your night to strength train or do a high-intensity workout. You want to do it, but fatigue and lack of sleep is zapping your motivation. Should you skip your workout and relax or push through despite your fatigue?

Train or Not?

If you’re sick or only had a few hours of sleep, working out is counterproductive. When you’re fatigued or not feeling well and your energy reserves are low, the risk of injury is higher since you may be sloppier with your form. If you’re tired, your mind can drift, and you end up injured. Plus, your reaction time may be delayed. Some people see training through fatigue as a badge of honor but not if you end up injured.

But what if you’re tired but not sure if you’re fatigued enough to skip? In some cases, exercise can be a pick-me-up and a fatigue buster. Studies show that people feel more invigorated once their bodies start moving and the blood starts pumping. It makes sense, doesn’t it? Exercise ramps up your sympathetic, or fight-or-flight, nervous system, so you feel more energized after exercise than you were before.

If you’re unsure whether you’re too fatigued to exercise, try working out for 10 minutes and see how you feel. Should the fatigue subside, keep going. If you still feeling exhausted, rest instead. Working out when you’re feeling wiped out is counterproductive.

The Impact Fatigue Has on Your Body

Another problem with working out when you’re exhausted is it can suppress your immune system. If you’ve had less than 6 hours of sleep or several nights of poor sleep and worked all day, your cortisol level is already high from fatigue and mental and physical stress. If you do an intense or long workout, it can further boost your cortisol level. In turn, the higher cortisol reduces the activity of immune cells that protect against pathogenic viruses and bacteria. If the flu is going around the office, elevated cortisol can increase your risk of catching it, not to mention one of the many cold viruses that circulate throughout the year.

As Bruce C. Corser, MD, director of the Sleep Management Institute in Ohio points out, “Even minor sleep disruptions can lower the body’s immune response and reduce resistance to illnesses such as the flu.” Combine lack of sleep with a hard workout and you compound stress on your body and further boost the risk of illness. That’s why we should avoid exhausting exercise. If you do a high-intensity workout, your body needs at least two days to recover before hitting it hard again. It’s okay to push yourself during a workout but not on a day you’re exhausted, sleep-deprived, or feeling under the weather. Listen to your body!

Modify Your Workouts

If you’re feeling fatigued but don’t want to skip your workout, modify it. Turn a high-intensity workout into a low-intensity one. This might be the perfect opportunity to pull out the yoga mat and focus on yoga poses. If you feel up to it, do a more invigorating yoga workout that builds strength and boosts your heart rate more, like power yoga.

You might also consider lifting weights but using lighter weights and higher reps. If you’re feeling extremely tired or under the weather, skip the cardio until you’ve rested up. A short, circuit workout will give you some exercise benefits without tiring yourself out as much. If you decide to work out, grab a steel water bottle and sip it while you work out. Hydration is always important but even a mild degree of dehydration can make you feel worse and reduce your performance if you’re not feeling up to par.

What if Your Fatigue is a Harbinger of Illness?

If you’re fatigued and are also achey or have a fever or other symptoms, take a rest day. Most trainers will tell you it’s okay to work out if your symptoms are from the neck up, like a stuffy nose, and you don’t have a fever. However, let your symptoms declare themselves. You may feel tired or achy because you’re in the early stages of influenza and working out with the flu is a no-no. Don’t take a chance, especially in the winter when viral infections are widespread. Remember, one day of rest won’t break you. Sometimes, relaxation and a good night’s sleep takes priority! You’ll come back stronger after a good night’s rest.

The Bottom Line

Don’t be afraid to take a rest day or modify your workout if you feel wiped out from a night of poor sleep or have symptoms of a virus. Also, make sure you’re balancing your training and aren’t doing back-to-back high-intensity routines or pushing your body too hard without adequate recovery. Moderation is key! Exercise places stress on your body. That stress leads to change, but you won’t get the full benefits unless you’re giving yourself enough recovery time between sessions.

Also, take a rest day at least once per week. Some trainers even recommend taking a rest week every few months during which you lighten up your training and reduce the intensity for optimal recovery. Listen to your body, keep tabs on how you feel, and don’t jeopardize your health and fitness by pushing too hard when your body is crying out for rest. Also, upgrade your sleep habits. Make sure you’re including enough sleep time in your schedule and work on creating healthy habits that help you sleep better at night. Growth and adaptations take place when you’re sound asleep, so make sure you’re getting at least 7 hours per night.



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