Exercise intensity not linked to mortality risk in older adults

Physical activity has been highlighted as one of the most important actions people of all ages can engage in to improve health, and data from observational studies show that early death is significantly reduced in physically active compared with inactive individuals.

For the findings, published in the journal The BMJ, the research team set out to evaluate the effect of five years of supervised exercise training compared with recommendations for physical activity on mortality in older adults (70-77 years).

The trial involved 1,567 participants (790 women and 777 men) living in Norway, with an average age of 73 years.In total, 87.5 per cent of participants reported overall good health and 80 per cent reported a medium or high level of physical activity at the start of the trial.

Of these 1,567 participants, 400 were assigned to two weekly sessions of high-intensity interval training (HIIT), 387 were assigned to moderate-intensity continuous training (MICT), and 780 to follow the Norwegian guidelines for physical activity (control group), all for five years.After five years, the overall mortality rate was 4.6 per cent (72 participants).

The researchers found no difference in all-cause mortality between the control group (4.7 per cent) and combined HIIT and MICT group (4.5 per cent).They also found no differences in cardiovascular disease or cancer between the control group and the combined HIIT and MICT group.

For example, the total proportion of participants with cardiovascular disease after five years was 15.6 per cent, with 16 per cent in the control group, 15 per cent in the MICT group, and 15.3 per cent in the HIIT group."This study suggests that combined MICT and HIIT has no effect on all-cause mortality compared with recommended physical activity levels," the study authors from the Norwegian University of Science and Technology in Norway.