Rigorous, or vigorous-intensity, exercise affects virtually every system of the body. In particular, vigorous-intensity exercise -- which can be defined as effort of seven to eight on a one to 10 scale -- provides significant health benefits for the respiratory system, the cardiovascular system, the musculoskeletal system and brain functioning. To attain important health benefits, the National Health Service recommend all adults under the age of 65 get at least 75 minutes of vigorous-intensity exercise a week -- or 2.5 hours of moderate-intensity exercise.
Rigorous exercise produces both short-term and long-term effects on the respiratory system, which includes the lungs, diaphragm and other organs involved in delivering oxygen to the body's tissues. According to biologist Dr. John W. Kimball, vigorous exercise can increase your body's needs for oxygen by 20 to 25 times. To deliver oxygen to your working muscles, you begin breathing faster and more deeply. In response to regular training, your respiratory system's capacity to deliver oxygen to body tissues will increase, in terms of both lung capacity and the number of oxygen-exchanging alveoli in the lungs. The diaphragm and other muscles involved in respiration will also strengthen in response to a long-term rigorous exercise habit.
Being essential in delivering oxygenated blood to muscles and other tissues, the cardiovascular system is also affected by vigorous-intensity exercise. In immediate response to rigorous exercise, the heart beats faster and more powerfully, increasing the volume of blood delivered with each pump. Blood temperature also rises. Blood is diverted from the digestive system and other nonessential systems to the tissues that need oxygen more immediately -- the muscles. Over the long-term, regular vigorous exercise causes the heart to become larger, stronger and more efficient at delivering oxygen to muscles. Most importantly, your risk of heart disease is greatly reduced with regular vigorous exercise.
The body's muscles and bones are significantly affected by vigorous exercise. Immediately, muscles contract, blood flow to muscles increases and muscle temperature rises. If you exercise regularly, muscles get both bigger and stronger, and muscular endurance improves. The tendons and ligaments connected to your muscles also grow stronger. In response to chronic vigorous exercise -- particularly strength training and weight-bearing exercises like jogging or skipping-- bones become denser, increasing in both width and density. Over the long-term, the beneficial effects of vigorous exercise on bone health are vital in the prevention of osteoporosis.
According to the Franklin Institute in the U.S,, rigorous physical exercise seems to improve brain health in numerous ways, including: warding off depression; helping prevent Alzheimer's and other age-related declines in brain functioning; and boosting cognitive abilities, such as memory, attention and planning. In one 2010 study, researchers found that among a group of 266 college students, students that more often engaged in vigorous physical activity, in bouts of 20 minutes or longer, had higher marks than students who less frequently engaged in vigorous exercise. The beneficial effects of vigorous exercise on your brain exercise might be most immediately apparent in terms of your mood -- acute exercise causes the brain to release "feel good" chemicals called neurotransmitters and endorphins.