There is no question that some amount of cardio exercise is beneficial for your health. Decades of medical research has shown us that cardio exercise is helpful for reducing obesity and all the problems that come with it. Cardio exercise helps to tone muscles and can help to strengthen your bones and ligaments, benefits that will become more important as you get older. However, as with all good things there are certain downsides. Did you know that too much cardio exercise can cause serious health problems? Well, it can. Before you get too excited, no one is saying that that you should throw out your running shoes and spend your days on the couch; however, there are some risk factors to cardio. Before you start your regimen, you should consider the potential problems and work to minimize them.
- Joint Damage and Other Orthopedic Injuries
Any high impact activity presents a high risk of joint problems. Anything that involves running or jumping can result in injuries like plantar fasciitis, shin splints and hip bursitis. Even people who only do limited amounts of cardio face some risk of injury; an excessive amount of exercise elevates that risk. The knees and hips are the joints that are most vulnerable to injury, especially in aging individuals. Your best bet is to involve yourself in low impact activities that place little or no stress on the joints. Options for this include using an exercise cycle, an elliptical machine or swimming. However, even with those safer options you may still face the risk of health issues if you do too much; it is a good idea to limit your cardio time to no more than 45 minutes per day.
- Heart Issues
Yes, cardio exercise is beneficial to your heart but only if it is done in moderation. If you overdo it, you actually increase your risk of having a heart attack. Consider the fact that a study published in the Mayo Clinic Proceedings journal showed that overdoing exercise can pose a threat to heart health. According to the study, more than an hour of daily exercise provides “diminishing returns” and can result in adverse cardiovascular effects. Atrial fibrillation and enlargement of the heart are two potential side effects of excessive cardio exercise; atrial fibrillation is also known as an “irregular heartbeat” and is problem that increases an individual’s risk of stroke. Another study presented at the Canadian Cardiovascular Congress states that overly long sessions of exercise caused the risk of heart problems to be increased by a factor of seven.
If you find yourself lacking in energy, cardio exercise is one way to change that. However, excessive cardio exercise can actually leave you with too much energy. A workout can raise your levels of adrenaline and leave you too amped up to go to sleep at night. This is especially so if you do your cardio later in the evenings. The solution to this is to arrange your schedule so that you do your workout in the mornings or earlier in the evenings. This allows you enough time to wind down before going to bed. Limiting the duration of your cardio exercise will also help with insomnia.
- Increased Appetite
An increase in your appetite can result from cardio exercise and may cause you to take in more calories. Eating more food is a side effect of cardio exercise for many people. The exertion causes their bodies to produce hormones that increase appetite with the net effect being that they start to consume more calories than they burn off. Their cardio exercise results in them gaining weight instead of losing it. A study published in the American Journal of Physiology shows that women who burned more calories than they consumed in a workout saw increased blood-concentrations of energy regulating hormones. Those are the hormones that signal the body’s desire for food. In other words, their bodies were telling them to eat to recover the calories they just lost. These effects are not limited to women as some men also have increased appetites after a cardio workout.
- Oxidative Stress
This is when your body produces unstable molecules called free radicals; these molecules can damage your cells, which results in more of these free radicals being produced. Excessive exercise causes too much oxidative stress for your body to fight. The result of all this is that you develop an increased risk of heart disease and cancer. It is important to note that pretty much every type of exercise causes some amount of oxidative stress, and researchers think that some amount of it is necessary, just not too much. Moderate amounts of oxidative stress actually help to make your body stronger.
- Elevated Levels of Cortisol
More than an hour or so of cardio exercise can stimulate the release of a hormone called “cortisol,” otherwise called the “stress hormone.” The purpose of this hormone is to change your metabolism in a way that enables you to better deal with stress. It provides you with increased energy for “fight or flight.” In the right amounts, cortisol can have health benefits in the form of muscle growth and improved heart health. The problem with excessive cardio exercise is that it can cause the hormone to accumulate in your system. Prolonged stress and high cortisol levels result in fat being retained and muscles being broken down. Elevated cortisol levels have been shown to result in the gain and retention of belly fat. Additionally, your immune system may be made weaker by higher levels of the hormone.
- Reproductive Problems
One study in the Canadian Journal of Applied Physiology showed that oxidative stress from excessive cardio exercise has negative effects on the male reproductive system. After four weeks of excessive strenuous cardio exercise, researchers found a decrease in the size of reproductive organs of men participating in the study; this was accompanied by reduced levels of testosterone. A similar study using rats found oxidative stress and sexual dysfunction.
None of this should be taken as a criticism of exercising. You need to exercise. Moreover, even with all of the health risks, the fact remains that people who do some cardio exercise are better off than people who do none. However, how much they do has a significant effect on how much benefit they get from it.
Age is a major factor in how your body handles cardio exercise and the issues it can cause. Older individuals should be particularly careful as bodies are not as resilient past a certain age; if you are over 40, you may face a longer recovery period when compared to someone in their 20s.