High muscle strength and cardiorespiratory fitness were significantly associated with a lower risk of all-cause mortality, a new study published in the British Medical Journal has found. The meta-analysis conducted by researchers from Australia, the UK, Italy and Brazil have reviewed 42 studies to determine the association of muscle strength and cardiorespiratory fitness with mortality in cancer patients .

Fitness reduces the risk of cancer deaths
"Overall, cancer patients with high muscle strength or CRF levels (when dichotomised as high vs low) had a significant reduction in risk of all-cause mortality by 31–46% compared with those with low physical fitness levels," the researchers found. "Similarly, a significant 11% reduction was found for change per unit increments in muscle strength. In addition, muscle strength and CRF were associated with an 8–46% reduced risk of all-cause mortality in patients with advanced cancer stages, and a 19–41% reduced risk of all-cause mortality was observed in lung and digestive cancers. Lastly, unit increments in CRF were associated with a significant 18% reduced risk of cancer-specific mortality," they have said.

This means, when cancer patients are divided into two groups—those with high fitness levels and those with low fitness levels—the high fitness group has a significantly lower chance of dying from any cause. Specifically, their risk is reduced by 31–46%. This shows that being physically fit can have a big impact on survival.

Even small improvements in physical fitness make a difference. For example, every small increase in muscle strength reduces the risk of death by 11%. Similarly, higher muscle strength and better CRF are linked to a 8–46% lower risk of death in patients with advanced cancer, who often face worse outcomes. This means that fitness benefits even those with more severe cases of cancer.

The benefits are especially notable in specific types of cancer, like lung and digestive cancers. Patients with higher physical fitness have a 19–41% lower risk of dying from these cancers.

Cardiorespiratory fitness also helps reduce chances of death directly caused by cancer. For every small increase in CRF, the risk of dying from cancer decreases by 18%.

“This highlights the importance of assessing fitness measures for predicting mortality in cancer patients. Given these findings, tailored exercise prescriptions to improve muscle strength and CRF in patients with cancer may contribute to reducing cancer-related mortality,” the researchers have said.