Exercise science

Science

Practical, evidence-based guides to training with heart rate zones.

The weekend warrior's guide to getting fit

Can two workouts a week really make you fit? The science says yes — if you make the effort count.

Read more →What is zone 2 training, and does it matter?

The easy pace everyone's talking about — what zone 2 actually is, and where it fits alongside hard efforts.

Read more →Why effort beats pace and distance

Heat, hills, sleep and stress all change how hard a workout feels. Here's why measuring effort is fairer than measuring speed.

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