Exercise can help you reach your fitness goals, but if overdone, it can also cause physical problems. Learn how to enjoy the health benefits of exercise while also staying safe.

Disease Risk

Regular exercise has a positive effect on many of the body’s systems and can reduce the risk of chronic disease.

Regular exercise can:

• Decrease the risk of type II diabetes by improving insulin sensitivity.
• Reduce triglyceride levels and increase good (HDL) cholesterol levels.
• Reduce the risk of heart disease by lowering resting blood pressure.

Studies suggest that people who engage in moderate exercise 5 times per week are 50 times less likely to suffer a cardiac event.

When paired with a decrease in body weight, regular exercise can also play a part in decreasing total cholesterol and bad (LDL) cholesterol.

Muscles and Bones

Research shows that adults lose one to two percent of muscle mass starting at age 50. This loss results in a reduced metabolic rate. Regular exercise, specifically strength training, helps to slow this loss by building muscle.

Weight-bearing physical activity (such as jogging, tennis, and strength training) provides the impact necessary to stimulate bone growth and improve bone health, which reduces the risk for fractures later in life.

Mental Wellbeing

Research has shown that both cardiovascular exercise and resistance training are equally effective at protecting against depression. Cardio is also linked to reduced anxiety. Other benefits include an improved ability to manage stress and improved sleep patterns.

Moderate vs. Vigorous

Experts recommend maintaining moderate intensity activity for at least 30 min, 5 times or more per week OR maintaining vigorous intensity activity for at least 20 min, 3 times or more per week. Moderate-intensity activities include brisk walking, recreational swimming, or bicycling. Vigorous activities are more intense (such as bicycling uphill or running). Use the "talk test" to determine your intensity level. If you can carry on a conversation while active, but you are working too hard to sing, then you are at a moderate intensity. If you are out of breath, you have moved into vigorous exercise.

How Much Is Too Much

The correct amount of exercise depends on your current fitness level. If you are sedentary, you can improve your health by adding even small amounts of exercise. However, the health benefits are gained in a linear-type progression, up to a state of moderate fitness. Beyond this point, health gains slow and they can eventually drop off due to over-training (refer to Figure 1).

This shouldn’t discourage you from incorporating more vigorous exercise when you are ready. It simply stresses the importance of starting at an exercise duration and intensity that is right for you. As your strength and endurance build, you can begin to challenge yourself with vigorous exercise.

People who jump into activities that are beyond their fitness levels (Weekend Warriors) greatly increase their risks of physical injury.

Don’t let these risks prevent you from starting a program. About 90 percent of heart attacks occur in a resting state, not during exercise. By selecting activities that match your current fitness level and by planning regular workouts, you can reap the benefits while reducing most risks associated with exercise.

Lori Rice, M.S., is a nutritional scientist and author with a passion for healthy cooking, exercise physiology, and food photography.