Incidental Activity Is Associated With Large Reductions in Cardiovascular Events and Mortality

What is the impact of incidental, nonstructured bouts of physical activity on cardiovascular events and mortality?

Short bouts of moderate or vigorous physical activity that are part of daily life are associated with a 24% to 50% reduction in cardiovascular (CV) events and mortality. Most Europeans do not exercise formally, but many of their cities are built for walking and cycling, thus, people get their exercise during their daily activities. There are two lessons here. First, we should encourage our patients to maximize informal exercise by parking as far from the store entrance as possible, taking the stairs, walking their dog, and walking to accomplish shorter errands. Second, we should take action in our communities to create safer spaces for walking and cycling. (Level of Evidence = 2b)

Most adults do not exercise regularly, at least not if we define exercise as structured sessions of 30 minutes or longer dedicated to an aerobic exercise. But what about the activity we experience in our daily lives? The study, based on data from the UK Biobank, asked 103,684 participants to use a wrist-worn accelerometer for 7 days between 2013 and 2015. Separate analyses were performed that excluded those with self-described poor health, a body mass index of less than 18.5 kg/m², smokers, and frail adults to avoid reverse causality (ie, being healthy leads to exercise, rather than exercise leads to being healthy). At baseline, the participants' mean age was 62 years, 44% were male, 97% were White. A sophisticated Random Forest algorithm classified activity as light (2 to 3 metabolic equivalents [METs], such as folding clothes or washing dishes); moderate (3 to less than 6 METs, such as walking briskly); or vigorous (6 or more METs, such as actively playing with children, short bursts of running, or fast walking). At baseline, the mean minutes of each activity level per day were 103 for light, 29 for moderate, and 7 for vigorous. Participants were followed up until late 2022, and major adverse cardiovascular events (MACE; eg, nonfatal myocardial infarction, heart failure, CV death) were obtained from hospital records and death registries.

Although all levels of physical activity showed inverse associations with MACE, CV mortality, and all-cause mortality, the associations were strongest in analyses for moderate and vigorous levels of activity. Approximately 3 minutes of moderate exercise had a reduction in serious adverse events comparable to 1 minute of vigorous exercise. Benefit plateaued at about 30 minutes per day for vigorous incidental exercise and less than 60 minutes of moderate incidental exercise. The reductions in risk were substantial: for 5 minutes per day of vigorous activity, the hazard ratios were 0.62 for CV mortality, 0.75 for MACE, and 0.76 for all-cause mortality. For approximately 24 minutes of moderate activity per day, the hazard ratios were 0.50 for CV mortality, 0.60 for MACE, and 0.53 for all-cause mortality. The greatest associations between duration of activity and benefit occurred at 14 minutes for vigorous and 35 to 50 minutes for moderate activity. Analyses that excluded frail people and those with poor health tended to increase the strength of the associations.