Track resting heart rate trends.
Resting heart rate is one of the cheapest useful health markers, but it is a trend instrument rather than a snapshot. The band places today's figure against adult norms, with a small allowance above fifty because resting rate drifts upward with age. The comparison against your own thirty-day average is the part worth acting on: a sustained fall of several beats generally reflects genuine aerobic adaptation, while a sustained rise of the same size points at illness, poor sleep, alcohol, heat or accumulated training load — usually in that order of likelihood.
Resting heart rate assessment
Percentile estimate = 100 - (RHR - 40 - age allowance) x 2.2; trend = current RHR - 30-day average
These figures are estimates based on population-average formulas and are intended for training and recreational planning only. They are not medical advice. Consult a qualified health professional before starting or changing an exercise, recovery or cold-exposure programme, particularly if you have a cardiovascular condition, are pregnant, or take medication that affects heart rate or thermoregulation.
Immediately on waking, lying still, before sitting up or drinking coffee. Anything later in the day measures activity and digestion as much as cardiovascular fitness and will not compare against previous readings.
Typically five to ten beats over three to six months of consistent aerobic work, with most of the change in the first eight to twelve weeks. Faster drops usually reflect a measurement change rather than an adaptation.
A rise of more than about seven beats sustained over a week without an obvious cause warrants attention, as does any resting rate consistently above 100. Both are worth raising with a clinician rather than training through.