Is Less More When Exercising? 8 Risks of Overtraining - Dr. Axe

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Is Less More When It Comes to Exercise? 8 Risks of Overtraining 


Risks of Overtraining - Dr. Axe

While regular exercise has a ton of proven benefits — lowering stress levels, giving you more energy, better managing your weight and improving heart health — this doesn’t mean that overtraining can’t cause the opposite types of effects. Despite what some people assume, due to the chronic stress it places on the body, the risks of overtraining are just as great as doing no exercise at all.

Not giving your body and hormones the time to adjust to exercise can cause injuries, mood problems, negative changes in your metabolism and “burnout” within a couple of months’ time. While too much exercise alone might not be the sole reason for negative symptoms in some people, overtraining combined with stress from other factors like imbalanced hormones, a poor diet, and a lack of rest or sleep can all accumulate to serious bodily damage.

When someone experiences symptoms of overtraining, it’s essentially their body letting them know that the total amount of stress on the athlete’s body is exceeding their capacity to recover and cope. To be a long-term health asset, the type of exercise you do should make you happier and more energetic, not the opposite. If you’re engaged in an exercise that’s always leaving you too tired, feels forced and doesn’t increase your love of life, you’re truly not doing yourself any favor.

While exercise threshold differs from person to person, most experts recommend sticking to about half-hour to one hour per day, most days of the week, but not everyday, to get the most benefits from exercise. It’s important to rest between workouts and take at least one full rest day every week — and sometimes even more like 2–3 depending on your goals and level of exercise intensity.

How Do You Know If You’re Overtraining?

The negative effects of overexercising can begin cropping up for people at different points, so it isn’t easy to pinpoint what the upper limit for you or anybody else might be. In order to help you prevent yourself from doing damage, it helps to know what happens to the body when you’re under too much physical stress, this way you can recognize the warning signs.


Here are several signs of overtraining that’ll tell you when you’re pushing yourself a bit too far:

  • Changes in your heart rate
  • Trouble sleeping
  • Increased soreness
  • Joint pain
  • Moodiness, anxiety or depression
  • Chronic fatigue or exhaustion
  • Changes in your appetite
  • Feeling more thirsty than usual
  • Digestion issues
  • Irregular periods or changes to your menstrual cycle

If you’ve just started a workout routine and notice some soreness or changes in your appetite, weight or sleep schedule, this likely isn’t something to be too concerned over. But if you’ve been exercising for a while and have slowly increased the hours you spend training each week, you’ll want to keep an eye out for developing symptoms.

Every now and then, such as in preparation for a marathon or sporting event, brief periods of overtraining can be a part of healthy regime and shouldn’t result in too much damage if done for a short period of time. However, chronically overtraining is capable of causing serious health problems, some that can take years to reverse and overcome.

The worst example of overtraining is rhabdomyolysis, a complex condition involving the rapid breakdown of skeletal muscle that causes muscle proteins and other muscle constituents to leak outside of cells and into the bloodstream.

Related: The Fitness Tracker: Tech that Boosts Your Weight Loss Efforts

8 Ways Overtraining Hurts You

1. Raises Cortisol Levels and Might Make You Gain Weight!

People battling weight gain are repeatedly told that they simply need to exercise more and cut calories, but in reality this is damaging to the metabolism and might totally backfire. Compared to shorter, but more intense workouts (like high-intensity interval training or HIIT workouts), doing many hours of steady-state exercise (like running) can actually result in lower metabolic and fat-burning potential.

Because of the way exercise impacts your hormonal status, fat metabolism can actually decrease with excessive, intense cardio exercise because it elevates cortisol levels, which winds up impairing insulin sensitivity. (1High cortisol levels are associated with fat-storing, as is being resistant to insulin that controls blood sugar. (2) Weight loss potential can also decrease fat-burning by convincing your body that it is “starving,” which means you’re unknowingly going to hold onto every precious calorie you eat in order to ensure survival.

If you live in a calorie deficit because your exercise level is too high and food intake is too low (especially if you are stressed out on top of that), your body gets the message that it must slow down all functioning to conserve energy. You can wind up entering a catabolic state that causes changes in your level of hunger and thirst — in fact, dehydration and intense cravings for sugar or salt are associated with overexerting yourself.

Another important factor is this: research shows that without even knowing it, most people end up eating more when exercising often in order to make up for the calories they burned. In that sense, doing 30 minutes of cardio may be better for weight loss than doing 60 minutes of cardio! That’s to say if you wind up feeling fatigued and having an out-of-control appetite due to running yourself into ground, taking it easy and eating a nutrient-dense diet with more calories might be exactly what you need to recover.

2. Can Lead to Adrenal Fatigue or “Insufficiency”

While training in moderation undoubtedly has positive effects on hormonal health, studies show there’s a “point of diminishing returns.” Too much exercise without proper rest can cause chronic stress and is linked to problems in the adrenal gland. (3) A severe type of adrenal fatigue from overtraining called “Overtraining Syndrome” (OS) is capable of causing adrenal insufficiency, in which the adrenal glands become so depleted that they stop producing enough of the crucial “stress hormones,” including cortisol and types of adrenaline.

The Department of Kinesiology at Texas A&M University describes overtraining syndrome as “chronic fatigue, burnout and staleness, where an imbalance between training/competition, versus recovery occurs.” The result? Ongoing fatigue, loss of appetite, difficulty sleeping, nutrient deficiencies and even the need for hormone replacement therapy is a type of serious condition called Addison’s Disease develops.

3. Causes Changes in Moods and Sleep Patterns

Just like with adrenal insufficiency and overtraining syndrome, the glands that normally control the production of hormones responsible for keeping your mood perky begin to dysfunction when your body is under too much stress. A lot of studies show dysfunction of the adrenal axis in overtrained and stressed athletes, sometimes to the point of suffering from insomnia, lack of motivation, irritability, anxiety or depression.


Experiencing a combination of nervous and endocrine (hormone) system changes can keep you up at night and lead to insomnia, or wake up you up very early in the morning and prevent your from falling back asleep — which leaves you groggy and unable to focus the following day.

And because your brain has a hard time producing enough “happy hormones” to complete with cortisol levels that are skyrocketing, overexercising is associated with moodiness, fatigue and even depressive symptoms like suicidality. (4) A 2013 study conducted by the Department of Psychiatry at Miami University found that among four different patient populations, overtraining coincided with increased depression symptoms and suicidal behaviors related to growing pain insensitivity.


Overtraining - Dr. AxeOvertraining - Dr. Axe

4. Can Negatively Impact Libido, Menstrual Cycles and Fertility

Too much exercise can negatively impact production of sex hormones (like testosterone and estrogen) associated with libido, fertility and reproductive health. However, unfortunately millions of men and women, particularly young women, overdo it every day. Termed the “Female Athletic Triad,” this complex condition in females caused by overtraining and eating too few calories can result in menstrual dysfunction, low energy and decreased bone mineral density. (4)

You don’t need to be a professional athlete to experience these effects — any woman who overtaxes their body too often can develop this condition.

Not to say that overtraining doesn’t have risks for men too, but women’s bodies appear to be especially sensitive to high levels of stress, exhaustion and operating in a calorie-deficit. When your body gets the signal that it’s being worked too hard, it causes your stress hormones to fire at a higher rate, which can lead to symptoms similar to PMS, including acne, insomnia, low libido, food cravings like sugar addiction, and other hormone malfunctions.

5. Leads to Muscle Wasting and Decreased Strength

Ever hear that you don’t actually grow stronger during your workouts, but instead during the time afterwards when you’re recovering and sleeping? Your muscle tissues can’t rebuild themselves fast enough when you don’t give yourself enough rest in between workouts.

The process of muscle recovery and rebuilding broken-down muscle tissue can take several days, so if you exhaust already fatigued muscles before they’re ready, you won’t see gains in terms of strength and more endurance. Since you’ll be running on a low energy supply, instead your body might start burning your own hard-earned muscle for fuel.

6. Raises Inflammation and Lowers Immunity

Overtraining can increase oxidative stress and damage, which leads to aging and illness. When your hormone levels abnormally fluctuate and your joints and muscle tissue become overly fatigued, you risk increasing inflammation — which results in illness, swelling and pain that won’t seem to go away easily. Being overly fatigued can depress the immune system largely by raising cortisol levels and inflaming the body. (5)

Your immune system stops functioning properly when in “starvation mode,” and you’re more likely to become sick and heal more slowly. Why does this happen? Basically if your body only has so much energy to go around, it’s going to prioritize and use that energy to sustain things that you rely on to survive — such as your heart beating, lungs breathing, digestive organs functioning and brain thinking. While all of these functions are compromised when you overtrain for a long period of time, immunity (along with digestion and reproductive health) is one of the first things to decline.

Overtraining is associated with increased risks for infections, including respiratory tract infections. T-helper lymphocytes are one crucial aspect of immune function. They’re responsible for killing foreign pathogens and producing antibodies, but exercise-related immuno-suppression due to tissue trauma suppresses the body’s ability to produce these helpers, and therefore leaves you more prone to becoming sick. At the same time, higher levels of stress hormones (cortisol and catecholamines) make it harder to heal and regain energy.

7. Can Cause Heart Damage

While moderate exercise is important for cardiovascular functioning, doing “too much of a good thing” can be antagonistic to heart health. Studies of over-exercisers (such as some marathoners) have found higher rates of cardiac events than moderate exercises and elevated levels of scarring on heart tissue. (6)

Long-term excessive endurance exercises (including marathons, ultra-marathons, ironman distance triathlons, and very long distance bicycle races) might negatively impact the structure of the heart and arteries, especially when the athlete isn’t replenishing with plenty of calories and sleep. High amounts of stress placed on the heart can potentially cause volume overload of the atria and right ventricle of the heart, thickening of the heart valves (myocardial fibrosis), heart beat arrhythmia, coronary artery calcification, changes in blood pressure (diastolic dysfunction) and artery wall stiffening.

You might notice that overtraining can also result in an altered resting heart rate, since the body is working on overdrive in the same way that it does during an emergency “fight or flight response.” One way to monitor if this is happening? Check your morning heart rate after getting up and track how it changes depending on your level of activity that week.

8. Interferes With Electrolyte Balance

Your muscles rely on a delicate balance of fluids (especially water) and electrolyte nutrients — including magnesium, sodium and potassium — to stay active and healthy. Even your heart, arguably the most important muscle in your body, can’t function the right way when you’re chronically low in potassium or these other nutrients due to overexerting yourself.

When you exercise, your muscles use up extra carbohydrates, electrolytes and fluid, and you’re often perspiring at the same time, which lowers your stores even more. (7) Your magnesium stores get used up during activity, which can lead to anxiety, insomnia, depression and a long list of other disorders. (8) This is also a risk because many people are already magnesium deficient — so too much exercise only adds to the problem. That’s why it’s important to both refuel after workouts with nutrient-dense foods and to give yourself time to recover so your body recalibrates.

Stop Overtraining and Do This Instead!

Even though our culture often preaches the message that “eating less, exercising more” is the key to health and weight control, as you can see, there’s definitely a safer way to go about things. Exercise is important, granted, but not the excessive type that causes you to feel very tired, overly hungry (or not hungry enough) and anxious if you missed a workout.

Instead, I recommend you try a new approach, where you focus on actually doing less exercise, just in a different, smarter way.

Shorter bouts of higher-intensity exercise, coupled with weight-bearing (or strength) movements (like a kick-butt kettlebell workout) that’s tailored to your own goals and needs, is now considered the exercise gold-standard when it comes to accomplishing more in less time. High-intensity interval training has gained attention for providing the same health benefits (or even more) as extended steady-state cardio sessions, only in a fraction of the time invested.

Alternating between intense periods of work — usually at about 85 percent of your max heart rate or more — followed by intervals of brief rest, results in an “afterburn effect” that burns more calories (even after you’re doing working out) and keeps you from dedicating hours to exercise. Because HIIT workouts, Burst training or sprinting fast reduces the amount of time the body spends in stress mode, it also lowers the stress response. Yet Burst training can still help you lose weight fast in a healthy way.

When it comes to your body composition, doing too much cardio does not promote muscle growth as you learned, and might actually break down existing muscle. But think of the athletic build of a sprinter, on the other hand: They’re normally muscular, fit and seem full of life.

So, as opposed to spending long periods doing “traditional cardio” like running on a treadmill, here are some of the many benefits of switching up your workout routine by kicking up intensity, lowering duration and very important, resting when it’s appropriate. Here are some of the health results of exercising in this way:

  • Improved blood cholesterol profiles
  • Increased energy levels and mood (from a boost in endorphins, serotonin, and dopamine, which give you a natural happiness high)
  • Decreased blood pressure levels
  • Increased oxygen use by muscles
  • Better removal of metabolic waste from muscles during resting periods
  • Increased insulin sensitivity (lower risk of diabetes)
  • Increased resting metabolic rate (meaning your body can burn more calories all day!)
  • Reduced risk of stroke, acute coronary syndrome and heart disease
  • And of course more time to yourself to do whatever makes you happy!

How can you do HIIT or Burst-training workouts safely without burning out or injuring yourself? The key is to start gradually and to rest in between tougher workouts. The beauty of HIIT is that it can be done in as little as 15–20 minutes at a time, and doesn’t require a daily commitment. In fact, it’s important to take days off in between intense workouts because this is when “the magic happens” — your body repairs itself and gives you noticeable gains in terms of speed, stamina and strength.

Aside from trying to incorporate some resistance training and HIIT-style exercises into your weekly routine, some people also prefer to focus on doing some sort of “happy movement” daily instead of thinking about exercise as something they “have to do.” Going for walks (especially outdoors), dancing, doing yoga, cycling and swimming are all examples of enjoyable exercises that can be done almost daily when performed in a healthy, moderate way.

In fact, this is the way that many of the healthiest populations on earth stay active: Walking around and staying busy throughout the day, gardening, doing errands by foot, and practicing hobbies or sports that involve being up on your feet.

The bottom line is that you must learn to listen to your body and judge when “enough” exercise turns into “too much.” Give yourself eight hours of sleep a night (sometimes more), take full rest days to relax, and remember to eat enough calories from high energy and performance foods to support your level of activity.

Overexercise is a real danger if you work out every single day or more than once a day, if you have to make yourself exercise despite feeling wiped out, and if you do cardio or sprint workouts too often while only focusing on burning calories. There’s a sweet spot for everyone, and it’s up to you to discover what that amount is, so judge how you feel and work in greater partnership with your body — this way the right amount of exercise comes naturally to you.

Read Next: The Afterburn Effect — How to Burn More Fat After You Exercise

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