You may think that doing cardio for a longer duration may boost overall strength but long bouts of cardio may do more harm than good. Pushing your heart too hard can make it stiff. This can cause trouble in maintaining a regular heart rate as excess cardio can stress the right ventricle of heart which is responsible for pumping blood.
If your daily cardio lasts for more than 60 minutes, it may impact your health. Athletes who do more than 10 hours of intense cardio in a week can damage their heart, which may never get healed.
When good exercise goes bad
Doing cardio is beneficial as it raises your heart rate which in turn raises the amount of oxygen in the blood. It also increases endorphin that acts as a natural painkiller. Aerobics, which is also a type of cardio, strengthens the immune system, helps to pump your blood more efficiently and increases stamina. But stretched cardio session may harm your body that can lead to negative effects like:
Reduced metabolism that hampers weight loss:
Whenever you exercise, it burns both fat and muscle. But the amount of muscle you burn is minimal. Doing cardio in excess can increase the risk of more muscle burn. This happens as the body struggles to keep up with the increased level of energy. It weakens your metabolism and hampers the process of weight loss.
Interrupted menstrual cycle:
If your progesterone level is chronically high, it can increase hormones like testosterone and estrogen. When the balance between progesterone and estrogen gets disturbed, it leads to irregular menstrual cycle and may also cause acne.
Your body remains soft no matter how much weight you lose:
It’s time to get happy when you see those scales falling. But losing weight doesn’t necessarily mean you are getting the type of body you want. Your body composition (i.e. the ratio of fat to lean tissue) determines the shape that your body takes. Cardio reduces both body fat and lean muscle tissue. By this you may get a smaller version of your body and not the required one.
Trouble in sleeping, especially if you are working out in the afternoon or evening:
If you have trouble in sleeping and find your workout challenging, your overdose of cardio may be the reason behind it. Your cortisol (stress hormone) level increases at night which leads to sleeping problems. Ideally your cortisol levels should be high in the morning and should lower down by night. So, instead of working out in the evening, prefer doing it in the morning.
Your body desperately holds onto fat:
Too much cardio can burn your muscles. This can impact your metabolism and shedding fat becomes more difficult.
Weakened immune system:
Excess cortisol release, which not only contributes to catabolism (catabolic state is the one in which your tissue breaks down) but also chronic disease. Cortisol, the major stress hormone, should be high in the morning and low by afternoon, staying down through bedtime. When cortisol is high, your blood sugar and blood pressure go up, you store more calories as fat- especially around your abdomen. This also suppresses your immune system.
But how do you know you are doing too much? Here’s a list of questions and if you answer yes to more than six questions then may be you are overdoing cardio.
– Do you generally feel lethargic and fatigued throughout the day?
– Do you have trouble in sleeping or feel like you’re not well rested even after sleeping for adequate number of hours at night?
– Has your physical performance (strength, speed, endurance) gone down rather than getting better?
– Are you getting sick more often than normal?
– Has your body fat dropped below healthy levels according to your height?
– Has your body fat not dropped at all?
– Has your menstrual cycle become irregular?
– Do you have trouble recovering between workouts?
– Have you experienced an injury such as a stress fracture, broken bone, or other chronic pain?
Recommended amount of cardio
An average adult requires 150 minutes of cardio in a week. Your heart rate should be between 50 to 80 per cent of your maximum heart rate to get the full benefits of cardio exercise.