Understanding training

Aerobic vs strength, intervals, VO2 max and intensity — the basics behind every workout.

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• Can a gentle yoga session be the right workout on a low-recovery day?

  Gentle yoga is a light-to-moderate workout that keeps you moving with little strain. On low-recovery days, pick slow styles and skip vigorous flows.

• How Does Exercise Intensity Decide Whether You Burn Fat or Carbs?

  Exercise intensity determines your fuel mix, your training zone, and even how hard pregnant women can safely push.

• How Much Aerobic Exercise Do You Actually Need This Week?

  WHO guidance says 2.5 hours of moderate aerobic exercise weekly cuts health risks, but even 75 minutes helps — here's the science and history behind that number

• How Should Strength Training Change When Your Daily Condition Score Is Low or High?

  How to align strength training with a 1–5 daily condition score, from warm-up and form to recovery-aware workout planning using Apple Watch data.

• Is an easy bike ride a smart choice when your recovery is low?

  Cycling is low impact, so an easy spin suits low-recovery days. Hard rides and long climbs still need fresh legs and a good bike fit.

• Should you run hard, easy, or not at all on a low-recovery morning?

  Running rewards consistency, but its impact adds up. Use your recovery score to choose between a quality session, an easy jog or a walk-run day.

• What Does VO2 Max Really Tell You About Today’s Workout?

  VO2 max is your aerobic engine size. Here’s what it measures, how it’s tested, and how to pair it with 1–5 readiness scores when planning today’s training.