Please read these explanations carefully to make sure HEAT is applicable to your case.

1) HEAT is to be used for assessments at the population level: for groups of people and not for individuals.

2) This tool is designed for habitual behaviour, such as walking for commuting, or regular leisure time activities.
Do not use it for the evaluation of one-day events or competitions (such as walking days etc.), since they are unlikely to reflect long-term average activity behaviour. HEAT is meant to be applied for walking of at least moderate pace (i.e. about 3 miles/hour or 4.8 km/hour)¹. Walking at this speed requires an energy expenditure that is considered to be necessary for health benefits².

3) HEAT is designed for adult populations (aged approximately 20-74 years).
This is the age range for which the used relative risk estimate is applicable (see box “more information on the relative risk estimate used“).Information on the relative risk in younger or older populations is insufficient for inclusion. If the age distribution in the assessed population is significantly different (much younger, much older) HEAT may over or under estimate the resulting benefits. In such cases, it is important to adjust the mortality rate which depends strongly on the age of the assessed population. However, HEAT should not be applied to populations of children, very young adults, or older people, since the relative risk used by HEAT does not include these age groups.

4) Studies on the benefits of physical activity for decreasing premature mortality have typically been conducted in the general population where very high average levels of physical activity are uncommon.
Thus, the exact shape of the dose-response curve is uncertain but it seems to level off above physical activity levels that are the equivalent of perhaps 2 hours of brisk walking per day. Therefore, the tool may not be suited for populations with very high average levels of walking (i.e. about 2 hours per day or more, e.g. mail personnel) which go beyond activity levels common in an average adult population. Caution also has to be applied when using the tool in predominantly sedentary populations, since the underlying risk estimates were derived from populations with a broad distribution of activity levels. HEAT could therefore slightly underestimate the effect in very sedentary population groups.

5) Knowledge of the health effects of walking is evolving rapidly. These projects represent first important steps towards an agreed harmonized methodology. In developing these tools, on several occasions the advisory group made expert judgements based on the best available information and evidence. Therefore, the accuracy of results of the HEAT calculations should be understood as estimates of the order of magnitude, much like many other economic assessments of health effects. Further improvements will be made as new knowledge becomes available.

HEAT is composed of 16 questions in total; depending on the route you take, some questions will be skipped.

If you have comments on the HEAT please email to heat@euro.who.int