Short, intense workouts: HIIT and "exercise snacks"
Physical ActivityKey points
- HIIT improved fitness about twice as much as moderate training in people with cardiometabolic disease.
- Three 1- to 2-minute bursts of vigorous daily activity were linked to 38% to 40% lower mortality.
- Vigorous means it is hard to talk.
- People with heart disease should check with their doctor first.
Interval training
A meta-analysis of studies in people with lifestyle-related cardiometabolic diseases found that high-intensity interval training increased cardiorespiratory fitness (VO2peak) almost twice as much as moderate continuous training (Weston et al., 2014). Cardiorespiratory fitness is one of the strongest predictors of longevity.
Bursts of activity in everyday life
In the UK Biobank, researchers used wrist accelerometers to study more than 25,000 adults who reported no exercise. Those who had about three bouts of vigorous intermittent lifestyle physical activity a day, each lasting 1 to 2 minutes, had a 38% to 40% lower risk of death from any cause and from cancer and a 48% to 49% lower risk of cardiovascular death than those with none (Stamatakis et al., 2022). The study was observational, but it suggests that every minute of vigorous effort counts.
The guidelines treat one minute of vigorous activity as roughly equal to two minutes of moderate activity (Bull et al., 2020).
How to start safely
- Warm up for 5 minutes first.
- Start with 2 or 3 short intervals and add more over weeks.
- Rest at least a day between HIIT sessions.
- Take the stairs fast instead of the elevator: an easy daily exercise snack.
Frequently asked questions
What is a simple HIIT workout?
After a warm-up, alternate 30 to 60 seconds of hard effort (fast cycling, running or stair climbing) with 1 to 2 minutes of easy movement, 4 to 6 times.
What counts as an exercise snack?
Any short burst of vigorous effort in daily life: running up a flight of stairs, carrying heavy groceries briskly, power-walking uphill or playing hard with kids.
Sources
- Weston et al. (2014). High-intensity interval training in patients with lifestyle-induced cardiometabolic disease: a systematic review and meta-analysis. British Journal of Sports Medicine 48(16):1227-1234. doi:10.1136/bjsports-2013-092576
- Stamatakis et al. (2022). Association of wearable device-measured vigorous intermittent lifestyle physical activity with mortality. Nature Medicine 28(12):2521-2529. doi:10.1038/s41591-022-02100-x
- Bull et al. (2020). World Health Organization 2020 guidelines on physical activity and sedentary behaviour. British Journal of Sports Medicine 54(24):1451-1462. doi:10.1136/bjsports-2020-102955
Keep reading
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Physical Activity tools
IPAQ: International Physical Activity Questionnaire (short)
Calculates your MET-minutes per week and your activity level.
QuizDo you meet the Physical Activity Guidelines? Check
Minutes of moderate and vigorous activity per week, plus strength training.
Quiz30-second chair stand test (for adults 60+)
How many times can you stand up from a chair in 30 seconds? Compared with CDC norms.
PDF · TrackerMonthly step tracker
Write down your daily steps and track your progress.
PDF · Log15-minute home strength workout + training log
A no-equipment routine with an 8-week rep log.
PDF · Card + trackerBalance exercises for adults 60+
A safe balance and leg-strength routine with a 4-week tracker.