Walking vs running — which is better for longevity?

The evidence doesn't actually favor running over walking for the core longevity outcome — if anything it's close to a tie, with walking scoring marginally higher here. Walking's case rests on a large meta-analysis linking higher daily step counts to lower all-cause and cardiovascular mortality, plus decades of cohort data (including the classic Harvard alumni study) showing a clear dose-response relationship. Running shows a comparable mortality reduction, including at low weekly volumes, per a meta-analysis and large cohort study. The practical difference isn't the health payoff — it's time efficiency (running gets you a similar risk reduction faster) versus sustainability and lower injury risk (walking is easier to keep up for life). Neither wins on the evidence alone; it comes down to which one you'll actually keep doing.