Most patients know that exercise is good for them and will help them live a longer, healthier life by reducing disease risk.  However, most individuals have at best an abstract idea of exactly what they need to do to reap the benefits of physical activity.  A recent study, published in the International Journal of Epidemiology, provides striking and simple guidelines.  This piece of research, which incorporates data from more than 1.3 million individuals across 80 studies, attempts to identify possible parallels between all-cause mortality levels and physical activity levels.  The study estimates combined risk ratios associated with defined increments and recommended levels, using random-effects meta-analysis and dose-response meta-regression models.  Here are the most notable findings:

• Subjects who exercised regularly had a lower mortality risk.
• Those who achieved 150 minutes of moderate activity each week reduced their risk by 10%.  150 minutes of vigorous exercise reduced all-cause mortality by 22%.
• 300 minutes of moderate intensity exercise per week led to a 19% reduced risk, and 300 minutes of vigorous exercise to a 39% reduced risk.
• Women saw a greater risk reduction than men.

Overall, risk reduction per unit of time increase was largest for vigorous exercise.  The bottom line is: encourage your patients to exercise, starting with a little at a time.  Something is clearly better than nothing!  However, as stamina increases, recommend incorporating higher intensity intervals lasting 20-90 seconds.  Depending on the patient’s health status this can involve slightly heavier breathing, to all-out effort.  All exercise is good; however, vigorous activity has the greatest impact on disease-risk reduction. Reference: Guenther Samitz, G, Egger, M, and Zwahlen, M. (2011). Domains of physical activity and all-cause mortality: Systematic review and dose–response meta-analysis of cohort studies.  International Journal of Epidemiology, 40(5),1382-1400