Table 1.

Comparing exercise intensities using various methods of measurement.

Exercise intensity	METs	HR	Borg rating of perceived exertion (RPE; 6–20 scale)	Subjective experience	Examples
Light	2.0–2.9	30%–39% HR reservea 57%–63% max HR	9–11	Movement that does not cause adults to sweat or breathe harder; easy to talk	Walking slowly (2.0 METs) Housework while standing (2.0–2.5 METs)
Moderate	3.0–5.9 METs	40%–59% HR reserve 64%–76% max HR	12–13	Causes some sweating and shortness of breath; can only speak short sentences	Brisk walk: 5.0 METs Bicycling (leisurely): 5.5–6.0 METs
Vigorous	≥6.0 METs	60%–89% HR reserve 77%–955% max HR	14–17	Causes considerable sweating and shortness of breath; can only speak 1–2 words	Swimming (leisurely): 6.0 METs Running 9.65 km/h: 9.5–10 METs

HR = heart rate; max = maximum; MET = metabolic equivalent; RPE = rating of perceived exertion.

^aHeart rate reserve is calculated by taking the theoretical maximum HR (208 − [0.7 × age]) and subtracting the resting HR (4). MET values refer to the energy expenditure, wherein 1 MET is at rest and 5 METs refer to expending 5 times the amount of energy a person would sitting at rest (2).