Participating in such formidable feats in the world’s fattest and most sedentary population is impressive. However, while getting super fit can make you into a human Ferrari, it is possible to worsen your health by over-training. Studies show over-training can deplete hormones, weaken your immune system, cause bone loss, increase the risk of injuries, slow healing, increase inflammation, and essentially burn you out. It’s no good to look like a lean, mean fighting machine when under the hood you’re aging too fast due to excessive exercise.
Adrenal Glands Give Clues to How Much Exercise is Too Much
Over-training causes the body’s adrenal glands, which manage stress, to secrete high levels of cortisol on a regular basis. High cortisol can cause bone loss, and muscle breakdown, create belly fat, increase sugar cravings, and lead to insulin resistance, a pre-diabetic condition that causes high blood sugar.
For others, excessive exercise causes low cortisol. Basically, the adrenal glands become exhausted from overuse and can no longer function properly. Low cortisol can lead to weight gain, reactive hypoglycemia (with dizziness, lightheadedness, and irritability between meals), muscle weakness, difficulty recovering from workouts, and a weaker immune system that makes you more susceptible to catching a virus or other infections.
In addition, most of today’s special-forces-style athlete must also work full-time, commute, care for a family, and run errands. Hectic schedules combined with lack of rest only add to the overall stress burden. Both high cortisol and low cortisol can worsen health and lead to chronic health issues.
How Much Exercise is Too Much for YOU?
It has been said that “one person’s workout is another person’s warm-up,” and the reverse is true as well. So this means many hours of extreme exercise each week may be appropriate for some people. Toleration for exercise intensity, duration, and frequency are unique to each individual. One must take into account the person’s general health, age, and fitness level. Jumping feet first into an elite training program might be appropriate for a healthy person in her mid-twenties. However, for a perimenopausal woman battling hot flashes and poor bone density, a gentler and more gradual approach is the safest way to avoid overstressing an already stress-burdened system.
How do you know if you are exercising too much? An adrenal salivary panel will chart your levels of cortisol, the body’s stress hormone, and show you whether it’s too low, too high, or just right. It is also important to pay attention to signals from your body that you may be overtraining. Symptoms of over-training include persistent tiredness, worsening strength and stamina, sleep disturbances, slow recovery, aching joints or limbs, injuries, and frequent illness.
Be watchful of these eight signs you are overtraining:
- You fail to complete your normal workouts because you’re getting weaker.
- You’re losing leanness despite increased exercise. Over-training can actually make you gain fat, especially around the middle.
- You’re lifting, sprinting, or doing high-intensity interval training every day. You need time to recover!
- You feel wired all the time and can’t sleep well. This means your “fight-or-flight” sympathetic system is in overdrive.
- You feel fatigued, sluggish, and useless, and can’t lose fat. Your “rest-and-digest” parasympathetic system is in overdrive.
- Your joints, bones, or limbs hurt. Walking up and down the stairs shouldn’t make you wince.
- You’re falling ill more often. Over-training has weakened your immunity.
- You feel terrible for hours and days after a workout. You should feel good from the endorphin rush of working out. If you don’t, you may be overdoing it.
This article was originally published in 2012. It is updated regularly.
 Sisson, Mark, Primal Blueprint.