Table 1

Descriptors of physical activity

IntensityObjective measuresWhat patient feels*Typical examples
Sedentary<1.6 METs
<40% HRmax
<20% VO2max
  • At rest with limited added movement

  • Sitting and reading

  • Watching TV

  • Driving a car

Light1.6–3.0 METs
40–55% HRmax
20–40% VO2max
  • Active

  • No noticeable change in breathing/sweating

  • Can be sustained for 1 hour or more

  • Slow walking (eg, around the house)

  • Light work while standing (eg, cooking, washing dishes)

  • Playing an instrument

Moderate3–6 METs
55–70% HRmax
40–60% VO2max
  • Increased breathing and sweating, but

  • Still able to maintain a conversation

  • Can sustain activity for 30–60 min

  • Brisk walk

  • Low movement racquet games (eg, doubles tennis, recreational badminton)

  • Water aerobics

  • Resistance exercise

  • Mowing the lawn

Vigorous6–9 METs
70–90% HRmax
60–85% VO2max
  • Feeling ‘out of breath’

  • Increased sweating

  • Can be difficult to maintain a conversation

  • Can sustain activity for up to 30 min

  • Jogging

  • Hiking

  • Swimming with effort

  • Higher movement racquet games (eg, singles tennis and squash)

  • Field/ball games (eg, soccer and basketball)

  • Cross-country skiing

  • Shovelling

High≥9 METs
≥90% HRmax
≥85% VO2max
  • Feels like giving 100%

  • All-out bursts of between 1 and 2 min

  • Intensity cannot be sustained for more than 10 min

  • Training/competing in most competitive sports

  • Racing or any all-out activity (eg, running, rowing, swimming, skiing and high-intensity intervals)

  • *These descriptions do not generally apply for symptomatic patients with chronic obstructive pulmonary disease. MET values for high-intensity activity may not be achievable for many patients with chronic disease, in which case HRmax or VO2max values are advised.

  • HRmax, theoretical maximal heart rate: usually estimated as (220−age)×0.9; MET, metabolic equivalent of task (1 MET=the energy to lie/sit quietly); VO2max, maximal oxygen uptake (adapted from Norton et al).65