{"id":11939,"date":"2026-08-04T16:15:12","date_gmt":"2026-08-04T15:15:12","guid":{"rendered":"https:\/\/blogs.bmj.com\/bjsm\/?p=11939"},"modified":"2026-08-04T16:17:37","modified_gmt":"2026-08-04T15:17:37","slug":"the-sweet-spot-for-light-intensity-physical-activity-does-it-depend-on-how-much-moderate-to-vigorous-intensity-physical-activity-you-already-do","status":"publish","type":"post","link":"https:\/\/blogs.bmj.com\/bjsm\/2026\/08\/04\/the-sweet-spot-for-light-intensity-physical-activity-does-it-depend-on-how-much-moderate-to-vigorous-intensity-physical-activity-you-already-do\/","title":{"rendered":"The \u2018sweet spot\u2019 for light-intensity physical activity: does it depend on how much moderate-to-vigorous-intensity physical activity you already do?"},"content":{"rendered":"

Why is this study<\/a> important?<\/h3>\n

Physical activity advice given to the general public tends to centre on moderate-to-vigorous physical activity (MVPA), the \u201cbrisk walking to running\u201d end of the activity intensity spectrum. For example, the World Health Organization (WHO) currently recommends 150-300 minutes of MVPA per week. However, many people, such as older adults, those with chronic conditions, or simply exercise novices, may find it hard to initiate or sustain MVPA.<\/span><\/p>\n

That\u2019s where light-intensity physical activity (LPA) comes in. LPA refers to activities that use more energy than sitting but don\u2019t leave you puffing, such as easy walking, household tasks, shopping, and gentle gardening. Growing evidence has linked LPA to health benefits, including lower mortality risk, yet LPA has only recently been incorporated into guidelines, and the language has been vague. For example, the Canadian 24-hour Movement Guidelines recommend \u201cseveral hours\u201d of LPA, leaving practitioners unsure how much LPA should be promoted.<\/span><\/p>\n

Our study tackles a practical question: How does LPA benefit health in the context of existing MVPA recommendations, and who benefits most from adding more light movements?<\/span><\/p>\n

How did the study go about this?<\/h3>\n

We used data from 71,715 UK Biobank participants who wore a wrist accelerometer for 7 consecutive days, giving objective estimates of daily minutes spent in LPA and MVPA. Participants were followed for a median of 8 years, during which 2,195 of them died.<\/span><\/p>\n

Instead of assessing \u201ccorrelation\u201d or \u201cassociations\u201d, which most existing studies examined, we used a causal inference approach to estimate the dose-response effect of LPA on mortality risk at low (5 mins\/day), medium (25 mins\/day) and high (67 mins\/day) MVPA, and also at MVPA levels matching the WHO guideline thresholds (low threshold: around 22 mins\/day, high threshold: around 44 mins\/day). We also created an app (click here<\/span>), to test \u201cwhat-if\u201d scenarios. For example: what would the 10-year risk of death look like if everyone did X minutes of MVPA and Y minutes of LPA?\u00a0<\/em><\/span><\/p>\n

What did the study find?\u00a0<\/span><\/h3>\n

Our study revealed several main findings:<\/span><\/p>\n