For most people, training is a chore. Endurance athletes, however, are not most people. As a coach, I have consistently found that ultrarunners, triathletes, and obstacle course racers need to be held back far more often than they need to be pushed. And while the willingness to work hard is an essential ingredient to success in endurance disciplines, it’s not the only one. The most successful athletes also have the restraint required to back off their training when they realize they’re doing too much.
How do you know when you’ve reached that point? Here are the top five indicators of overtraining.
Your Performance Is Tanking
The whole point of training is to get fitter. Thus, if you’re consistently training and, say, unable to hit your usual power numbers on the bike, or you’re bonking at shorter and shorter distances while running, then you know something is wrong. Loss of performance can result from a variety of factors, including illness and nutrient deficiencies. But if your training is the only thing that has recently changed, then the cause of a performance decline is almost certainly training too much.
You Feel Crappy
For decades, scientists have searched for the most reliable objective biomarker of overtraining. Everything from the amount of cortisol in the blood to the amount of testosterone in saliva has been considered. But a 2015 review by Australian researchers concluded that athletes’ own subjective assessment of how they feel is the most reliable indicator of overtraining.
This makes sense. An athlete’s internal perceptions of physical well-being are not arbitrary. There has never been an athlete who was totally crushing every workout yet feeling consistently washed out. Unlike hormones and other biomarkers, how you feel represents the totality of what’s going on in your body.
Changes in Heart Rate
A higher than normal morning pulse rate is a classic indicator of overtraining. Make a habit of measuring your heart rate every day as soon as you wake up. One morning with a higher than normal HR is nothing to worry about, but if this becomes a trend, you may need to cut back on exercise for a bit.
A fancier measurement called heart rate variability (HRV) can also be used to identify overtraining. HRV refers to subtle variations in the rhythm of the heart’s contractions. A healthy level of endurance training tends to increase HRV, whereas overtraining has the opposite effect. Many heart rate monitors measure HRV and provide training recommendations based on the results, as do apps such as HRV4.
You Dread Workouts
When your performance is tanking and you’re feeling crappy, it’s natural to start dreading workouts. A loss of motivation for training is an almost universal symptom of overtraining. If you find yourself looking for excuses to skip workouts, don’t blame your lack of discipline—blame your excessive training load and temporarily pare it down to a level that brings back the hunger.
Easy Days Aren’t Easy
One of the most overlooked effects of endurance training is its impact on the relationship between work rate, or how fast you’re going, and perception of effort, or how hard it feels to go that fast. When your training plan is working and you’re getting fitter, the same level of output—whether it’s 200 watts on the bike or an eight-minute-mile running pace—feels subjectively easier than before. When the opposite is true and even your easiest workouts start to feel hard, you’re probably training too much.
This was shown in a study conducted at England’s Birmingham University. Cyclists performed two weeks of normal training followed by two weeks of double their normal training. At the end of each two-week period, the cyclists were asked to rate their perceived effort level on the Borg scale at a work rate of 200 watts, which for them was a fairly low intensity. On average, the cyclists rated this easy effort as being 8.9 percent harder after the two weeks of double training loads.
The lesson here is simple: Pay attention. Even your gentlest workouts offer valuable information about how your training is going.