Muscle strength and cardiorespiratory fitness linked to improved cancer survival rates

24th January 2025

Good physical fitness combined with muscular strength could reduce cancer patient deaths, a recent study suggests.

Researchers found that tailored exercise plans may prolong life for people living with cancer and boost their chances of survival. The study, published in the British Journal of Sports Medicine, could have implications for clinical practice, with muscle strength exercises employed to increase life expectancy.

The international researchers, led by Edith Cowan University in Australia, pooled data from 42 studies published in English in five databases up to August 2023 to examine whether physical fitness could extend survival rates in cancer patients. The 47,694 patients in the studies had an average age of 64 and had been diagnosed with various types and stages of cancer.

Muscle strength was determined by handgrip strength measurements. Depending on age, a handgrip strength of below 13 kg to below 25 kg was classified as low strength for women. Low strength was classified as below 20 kg to below 40 kg for men. Cardiorespiratory fitness was assessed using either cardiopulmonary exercise testing (CPET) or a six-minute walk test (MWT).

The analysis suggested that both muscular strength and good physical fitness are associated with a significantly lower risk of death from any cause in cancer patients. Patients who maintained strong muscles and good overall fitness had a 31-46% lower risk of dying from any cause compared to those with poor muscle strength and low cardiorespiratory fitness. This risk continued to fall by 11% for each unit increase in muscular strength and 18% for each unit increment in cardiorespiratory fitness.

In patients with advanced-stage cancer (stages 3 and 4), muscle strength and cardiorespiratory fitness were associated with an 8-46% reduced risk of all-cause mortality and a 19-41% lower risk of death from any cause among those with lung or digestive cancers.

‘Our findings highlight that muscle strength could potentially be used in clinical practice to determine mortality risk in cancer patients in advanced stages and, therefore, muscle strengthening activities could be employed to increase life expectancy,’ the researchers concluded.

A previous study published in the same journal suggested that young men with a higher level of cardiorespiratory fitness had a significantly lower risk of developing several cancers in later life.

A version of this article was originally published by our sister publication Nursing in Practice.

High cardiorespiratory fitness linked to lower risk of dementia, study finds

22nd November 2024

Maintaining a good level of fitness could help prevent dementia, especially among people who are genetically susceptible to the disease, new research suggests.

The study published in the British Journal of Sports Medicine found that people with a genetic predisposition to dementia can reduce their risk by up to 35% by increasing their cardiorespiratory fitness. High levels of fitness are also associated with better cognitive ability, the researchers noted.

Involving 61,214 people, the study is one of the largest to assess the effect of fitness on cognitive function and dementia risk. Researchers at the Karolinska Institutet in Sweden used data from the UK Biobank to identify people without dementia between the ages of 39 and 70 and tracked their health over 12 years.

At enrolment, all participants took part in a fitness test that involved cycling on a stationary bike for six minutes. Cognitive function was also assessed using neuropsychological tests, and genetic susceptibility to dementia was determined using a genetic risk score for Alzheimer’s disease.

Over the 12-year study period, 553 people (0.9%) were diagnosed with dementia, identified through patient medical records. The researchers used statistical methods to calculate the link between physical fitness and cognitive health, as well as how genetic predisposition influenced the development of the disease.

Participants who had a higher level of cardiorespiratory fitness had a 40% lower chance of developing dementia compared to people with low levels of cardiorespiratory fitness. High levels of cardiorespiratory fitness were associated with a delayed onset of all dementia by 1.48 years.

For people who had a moderate or high genetic risk of developing dementia, high levels of cardiorespiratory fitness reduced all dementia risk by over a third.

Professor Weili Xu, professor in geriatric epidemiology at the Karolinska Institutet and author of the paper, said: ‘Our study shows that higher fitness is linked to better cognitive function and reduced dementia risk. In addition, high fitness could attenuate the effect of genetic risk for all dementias by up to 35%.’

The researchers cautioned that the study was observational only, and suggested that the rate of dementia cases may be underestimated by the UK Biobank population, which tends to be healthier than the average population.

Acknowledging the need for further research, Professor Xu added: ‘Our findings suggest that maintaining good fitness may be a strategy to prevent dementia, even among people with high genetic susceptibility.’

A version of this article was originally published by our sister publication Nursing in Practice.

Higher cardiorespiratory fitness in young men linked to lower risk of cancer

30th August 2023

Young men with a higher level of cardiorespiratory fitness have a significantly lower risk of developing several cancers in later life, according to the findings of a new study published in the British Journal of Sports Medicine.

It is already known that aerobic exercise induces interleukin-6 and suppresses a marker of DNA damage, which may account for a protective role in colon cancer. But whether being fit could reduce the risk of developing cancer in later life is far less clear.

For the recent study, Swedish researchers set out to assess the associations between cardiorespiratory fitness in young men and the incidence of site-specific cancer.

They turned to data held on men who underwent military conscription between 1968 and 2005 and for whom cardiorespiratory function was assessed by maximal aerobic workload cycle test at conscription.

The men’s level of fitness was then categorised as low, moderate or high, and those who received a cancer diagnosis before or within five years after the military conscription were excluded from the analysis.

Cardiorespiratory fitness and cancer

The team included 1,078,000 men, of whom 6.9% subsequently developed cancer in at least one site during a mean follow-up of 33 years.

A higher cardiorespiratory fitness was linearly associated with a significantly lower risk of developing nine different cancers. This included cancer in the head and neck (Hazard ratio, HR = 0.81), oesophagus (HR = 0.61), stomach (HR = 0.79), pancreas (HR = 0.88) and liver (HR = 0.60).

In contrast, a higher cardiorespiratory fitness significantly increased the risk of being diagnosed with prostate cancer (HR = 1.07) and malignant skin cancer (HR = 1.31).

While it is an observational study and no firm conclusions can be drawn about cause and effect, the researchers suggested that the findings strengthened the incentive for promoting interventions aimed at increasing cardiorespiratory fitness in younger people.