How Do You Know if You’re Overtraining?

How do You Know if You're Overtraining?

Regularly pushing past your limits has consequences that can derail your fitness journey. Here’s what you need to know.

By Aimee Layton, PhDUpdated February 22, 2022


As a bike racer and an exercise physiologist, I know from both personal and professional experience how tempting it can be to chase a goal and overdo it in the process. I see it in my lab all the time: Extremely fit people who’ve pushed themselves too hard, exercising at their peak day after day. The result? Symptoms like shortness of breath, an elevated resting heart rate and not seeing fitness gains despite working hard.

The good news is that this isn’t something the average exerciser needs to worry about. Most of us know how to listen to our bodies—whether that means skipping a workout if you’re super stressed or when your muscles are still sore from yesterday’s workout or you’re sleep-deprived. There are several built-in feedback loops in the body that help protect most of us from exercising to the point of cardiovascular or respiratory failure, but that doesn’t mean you can’t do damage along the way.

If you tend to push yourself hard day in and day out, it’s helpful to know the signs of overtraining and the problems it can cause so you’re able to meet your training goals without risking your health.

What Exactly Is Overtraining?

While there’s technically no medical definition of overtraining, there are a few indications that a person may be pushing themselves too hard, too often or in a way that won’t result in increased strength and fitness.

One indication is any orthopedic sign of overtraining, like overuse injuries. When this is the case, patients tend to report a gradual onset of muscle, joint or tendon pain that’s reproducible with a certain movement. For example, your glute starts hurting five minutes into a workout or your knee pain becomes sharp at mile six of a run. With these injuries, pain tends to get worse during exercise and may feel better when you rest.

When pain is felt in a specific place, such as your knee, hip, ankle or back, this is usually a sign of a biomechanical issue. With overuse injuries, the pain usually starts later in your workout. However, over time, the discomfort can occur earlier during exercise. If you ignore it, it will start hurting even when you’re resting. When this happens, you need to investigate whether it’s your form or your workout gear that’s causing the problem. If it persists, speak to your doctor.

Assess Your Risk of Overuse Injuries and Overtraining

Here are a few questions to ask yourself: Are my running shoes old? Am I not stretching enough after working out? Is my alignment off in my stride or pedal stroke? Am I relying too much on small muscles and not recruiting larger muscles to do the work? I always think of rowers with this last question. A rower may start with recruiting their glutes and quads, but as they fatigue, their form suffers, and they begin to pull with their back and arms too much. This is a classic form break that results in overuse injury over time.

For biomechanical problems, a reputable sports performance center can often help you find the root of the problem. Look for a center that has a large team consisting of doctors, physical therapists and exercise physiologists. You want a place that can rule out any broken bones, ligament tears or other acute injuries before addressing biomechanical overuse injuries.

The overtraining scenarios that are trickier to diagnose are the ones involving the cardiovascular and respiratory systems. Symptoms may include shortness of breath and feeling all-over fatigue or “tired legs” at low exercise intensities despite following a consistent fitness routine. Some patients talk about their sleep patterns being affected (exercise should make you sleep better, not worse) and that they seem to be more susceptible to head colds and other illnesses.

It may be tempting to dismiss these weird, nondescript symptoms, but they are important signs that the intensity of your workout may be too high with not enough rest and recovery workouts in between. In other words, your training is off balance. And in the way our bodies need a balanced diet, we need a balanced exercise routine as well. Of course, if these symptoms persist, you should speak to your doctor.

Why a Well-Balanced Fitness Routine Is Important

Good health requires a delicate balance between the sympathetic nervous system (what puts you in fight-or-flight mode) and the parasympathetic nervous system (the one that lets you rest). When you exercise, both of these nervous systems shift into gear. The sympathetic nervous system helps pump blood away from your stomach and into your muscles to help you run faster, lift heavier and push harder. The parasympathetic nervous system goes into standby mode until your effort is complete.

However, too much high-intensity exercise with not enough recovery leads to a shift in your sympathetic nervous system, essentially putting it into overdrive all the time. The result? You lose that ideal balance between both nervous systems and your heart doesn’t get a break from the constant “fight or flight” drive, even when you’re not working out.

This imbalance in your nervous system can also lead to an increased resting heart rate. A normal range for healthy adults is anywhere from 60 to 100 beats per minute, with lower resting heart rates implying more efficient heart function and better cardiovascular fitness. When your resting heart rate is higher than usual, a big push on the Peloton Bike or Peloton Tread might not elicit as high a heart rate as you’d expect for the effort you expend. This is actually your body’s genius way of regulating your cardiovascular system when you’re approaching your max heart rate.

Excessive high intensity exercise can lead to excessive inflammation in your muscles and also in the airways of your lungs, which is why you might start getting more head colds or produce lots of phlegm when you try to work out. Your diaphragm will get stronger with these high-intensity workouts and allow you to take deeper breaths, but there is a theory that if you spend an excessive amount of time at your VO2 max (your cardiovascular maximum), blood flow may be redirected away from your muscles toward your diaphragm in an effort to preserve lung function. This means that although you are working really hard, your legs aren’t getting stronger because your body is prioritizing lung function. While more research is needed in this area, what we do know is that regularly working at your VO2 max can do more harm than good.

If you start to notice some of the upper respiratory symptoms mentioned above, it’s important to question whether you’re pushing yourself too hard and, if so, consider giving yourself a break. If you continue overtraining, you may hit a plateau and see your fitness level decline despite training harder, or even experience something more serious like insomnia, injury, heart attack or stroke.

3 Ways To Avoid Overtraining

Here’s how I recommend hitting the sweet spot between high-intensity training sessions and leaving room for recovery.

1. Don’t Spend Too Much Time at Your Peak

A good estimation of your “peak”—when your heart and lungs are working to their upper-limit capacity—is your maximum heart rate. If you don’t know your maximum heart rate, an easy estimation is 220 minus your age. (Mind you, this is not the highest your heart rate can go, but rather it’s the highest rate at which your heart can sustain cardiac output for about a minute.) If you are dehydrated or have been racing or training for a long time and then sprint, you may see a higher heart rate. But for the purposes of training, we will use this equation as an estimated peak.Now, take 90 percent of that number; that is your top-end zone. For example, my estimated cardiovascular peak is 182 beats per minute (bpm). A heart rate of 165 bpm is approximately 90 percent of my peak heart rate. Therefore, I try not to spend more than 10 minutes consecutively above 165 bpm every workout. If I am racing or trying to PR, I may exceed that time, but then I make sure to follow up that workout with rest and recovery riding. If I am spending more than five to 10 minutes at once above 165 bpm during every workout, I may start to overtrain over the course of time. This advice is, of course, for the average person. An elite athlete or someone with health limitations may have a different top-end and can adjust accordingly.

2. Take it Easy if You’re Stressed

High-intensity exercise creates an inflammatory response in your body. This is how your body signals to repair the effects of stress. But sometimes that inflammation can occur in places that can’t repair or you don’t want stress to the tissue. For instance, breathing hard creates inflammation in your airways. Emotional or physical stress also produces an inflammatory response. Combining stress from exercise when you’re already in a state of emotional or physical stress because of something that’s going on at work or at home, or if you haven’t had enough sleep can sometimes make it hard for your body to process all of that inflammation and lead to a longer recovery time needed.Exercise can feel like an incredible release during hectic times. But remember, when you’re under a lot of stress, high-intensity exercise can create more stress internally and could set you back in the long run. Instead, choose a low-intensity workout, like a low-impact Peloton Bike ride, a walk on the Peloton Tread, yoga or meditation class.

3. Balance Vigorous, High-Intensity Exercise With Active and Passive Recovery Days

To avoid overtraining, rest and recovery are key. But that doesn’t mean you have to be sedentary. Both passive and active recovery can go a long way toward helping you recover from tough workouts.Think of active recovery as exercise that’s less intense than your usual workouts, which can be incorporated into your exercise session or afterward. For example, when you’re on the Peloton Bike, you might hold an easy cadence rather than pushing hard during an interval. Or the day after a 10 out of 10 workout, you might take a low-impact ride or a stretch class. The goal is to move your body without a focus on any kind of measurable effort, which will help to loosen your muscles and give your cardiovascular and pulmonary systems a break from working so hard.Passive recovery is exactly what it sounds like: Letting yourself rest completely, with either extremely minimal energy output or no effort at all. Maybe that means taking a stretch or meditation class or getting a massage. Maybe you spend a few hours cozied up in your favorite nook on the couch reading a book or watching your favorite show. Whatever rest days look like for you, know that recovery will help you reset for your next high-intensity training session.

Aimee Layton, PhD is a Peloton Member and paid consultant member of the Peloton Health & Wellness Advisory Council. Dr. Layton is an assistant professor of Applied Physiology in Pediatrics in the Division of Pediatric Cardiology and the Director of the Pediatric Cardiopulmonary Exercise Laboratory at Columbia University Medical Center / New York Presbyterian Hospital, where she plays an important role as one of the lead exercise physiologists in testing, exercise counseling and research.

This content is for informational and educational purposes only and does not constitute individualized advice. It is not intended to replace professional medical evaluation, diagnosis, or treatment. Seek the advice of your physician for questions you may have regarding your health or a medical condition. If you are having a medical emergency, call your physician or 911 immediately.