Strength training lowers the levels of hormones, such as estrogen and insulin, which are known to correlate with the development and progression of cancerous cells. Post-menopausal women who increase their physical activity lower their risk of breast cancer. 

Strength training alters the metabolism by developing lean muscle mass, which results in decreased exposure to the bile acids of the gastrointestinal tract. It reduces inflammation in the body and boosts the immune system, allowing the body to fight diseases and function properly.

Starting a strength-training program, even when diagnosed with cancer, can yield positive outcomes. 

Starting on a strength-training program as soon as possible after being diagnosed with cancer is highly recommended. After diagnosis, typically people slow down; stress, depression, and fatigue set in. Treatment tends to make a person less active, which aggravates the situation. 

Strength training lifts your mood and increases self-confidence. It makes you stronger, and improves your balance, making daily activities more comfortable to perform. You will have more energy and reduce the risk of losing bone mass (osteoporosis) that some cancer treatment can cause. One week of being bedridden produces the equivalent of 1-year bone loss. Contrary to popular belief, osteoporosis is reversible. Bone is alive and can regenerate. Strength training is the no1 scientifically proven sport to fight osteoporosis.

It can also help in shortening the length of time spent in the hospital by making your treatment more effective at destroying tumor cells, as it boosts your immune system. 

Studies conducted by the Canada Research Chair in Physical Activity and Cancer at the University of Alberta in Edmonton, Canada suggests that increased level of physical activity reduce the risk of cancer coming back.