Resting heart rate and training zones, explained

Resting heart rate

Resting heart rate is your pulse when fully at ease, ideally measured on waking before you get up. Typical adult resting rates fall somewhere in the region of 60 to 100 beats per minute, and it tends to be lower in people with good cardiovascular fitness.

Tracking it over time is more useful than any single reading. A resting rate that is consistently higher than your own normal can reflect stress, illness, poor sleep or overtraining, and is worth paying attention to.

Estimating maximum heart rate

Maximum heart rate is often estimated as 220 minus your age. It is simple and widely used, but the standard deviation around it is large — for a given age, individual maximums can differ by ten or more beats per minute either way, so the estimate should be treated as a rough anchor.

A more individual approach is to measure it during a hard effort under appropriate supervision, or to use a field test if you are healthy and experienced. For most general training purposes, the age-based estimate is adequate as a starting point.

The standard training zones

Training zones are usually defined as percentages of maximum heart rate. They describe the intensity at which you are working and the adaptations that training at that intensity tends to produce.

Zone 1 and 2 are the easy, conversational intensities that build aerobic base and are sustainable for long periods. Zone 3 is moderate. Zone 4 approaches hard, sustainable for shorter efforts. Zone 5 is maximal, sustainable only briefly.

• Zone 1 — very light, 50-60% of max — warm-up and recovery
• Zone 2 — light, 60-70% — aerobic base, conversational pace
• Zone 3 — moderate, 70-80% — tempo work, sustained effort
• Zone 4 — hard, 80-90% — threshold intervals
• Zone 5 — maximal, 90-100% — very short, intense efforts

Using the zones well

The most common mistake in training is spending nearly all of it in the moderate middle — too hard to be truly restorative, too easy to drive real improvement. A widely used approach is to keep most training easy, in zones 1-2, and concentrate the hard work into a smaller number of higher-intensity sessions.

Heart rate also lags effort, and it is affected by heat, caffeine, stress, hydration and fatigue. Use it as a guide alongside how you feel rather than as an absolute rule, and be prepared for the same effort to produce a higher rate on a hot or tired day.

The heart-rate reserve method

An alternative to percentage-of-maximum is the Karvonen method, which uses heart-rate reserve — the gap between your resting and maximum rates. It produces zones that are more individualised, because it accounts for your resting rate as well as your maximum.

The two methods give similar but not identical zones. Either is a reasonable framework; consistency matters more than which one you choose.