Friday tip: how to boost walking cardio fitness

Earlier this week, I held my breath walking past a construction site to avoid inhaling a drifting plume of dust. I gave up breathing for a good 12-15 seconds while ambulating as briskly as possible, which got me thinking about any potential health benefits of intermittently holding breath while walking.

Or, as the scientific literature calls it, voluntary hypoventilation.

I’ll say up front that “breath-hold walking" remains mostly a scientifically untested application, so everything you read in this post is more about potential benefits, based on credible research. With that acknowledgment, here’s what I’ll say:

Holding your breath in short bouts while you walk is a no-cost, low-impact way for healthy adults to layer a mild stress onto an easy activity. A handful of adjacent research suggests a payoff.

The logic comes from altitude and athlete training. Brief exhale-holds lower blood oxygen and raise CO2, and that mild stress is what may drive adaptation. The evidence that it could have health benefits comes from neighboring studies:

• Device-based intermittent hypoxic training — breathing low-oxygen air — significantly raised VO_2max in a 2023 meta-analysis, the clearest aerobic signal in this research, though that’s a stronger stimulus than any walking breath-hold.

• Voluntary breath-hold sprint training improved fatigue resistance and lactate handling in trained athletes.

• Intermittent hypoxia combined with walking improved walking speed and endurance in patients rehabilitating from spinal-cord injury.

• Breath-hold training strengthened breathing capacity — how much air swimmers could move and how forcefully — in competitive athletes.

The common idea for all the above is the act of training one’s tolerance to rising levels of CO2—the actual trigger for the urge to breathe—so that harder efforts feel easier sooner.

None of these studies tested breath-hold walking, and none enrolled healthy adults over 50. The one robust VO_2max finding comes from low-oxygen-air training, a more intense stimulus than holding your breath on a walk.

The effect of holding one’s breath while walking may be small, since the oxygen drop that powers altitude-style adaptation generally requires hard effort that walking doesn’t supply. But they’re not nothing.

Anyone with cardiovascular, blood-pressure, or respiratory conditions should avoid this admittedly experimental exercise. But if you’re like me, interested in how far you can safely push your limits, no matter how small or seemingly inconsequential, walking breath holds may be a fun way to add a moderate edge to that routine walk to/from the store, school, pharmacy…or just to wherever your car is parked.