Treadmill specs are full of numbers designed to look impressive — a couple of them are genuinely useful, and a couple are mostly there for the spec sheet.
Continuous horsepower vs. peak horsepower
Motor power is usually listed two ways: peak horsepower (the motor's brief maximum output) and continuous horsepower, or CHP (what it can sustain reliably over time). Continuous horsepower is the number that actually predicts how the treadmill will hold up under regular use — a motor that's only rated well at its peak but weak on continuous output will strain and wear out faster under sustained running, even if the peak number looks impressive on the box. As a rough guide, more serious or frequent runners generally want a higher continuous horsepower rating than someone who mainly plans to walk.
Belt size matters more for taller users and runners
The belt's length and width determine how much room there is for a natural stride without feeling cramped or risking stepping off the back at speed. Walkers with a shorter stride have more flexibility here; taller users and runners, especially at faster paces, benefit from a longer belt with real margin at both the front and back of a full stride.
Cushioning is a real tradeoff, not just a comfort feature
More cushioning reduces impact on joints, which matters for running and for anyone with joint sensitivity — but too much cushioning can feel unstable at faster speeds, since a firmer platform gives better feedback and stability for pushing off. Some treadmills offer variable cushioning across different zones of the belt (softer at the heel-strike area, firmer toward the front) as a middle ground.
The one thing people forget
Check the treadmill's actual folded dimensions and weight if storage space is a concern, not just whether it folds at all. Folding treadmills vary enormously in how compact they actually become and how easy the fold mechanism is to operate solo — a treadmill that "folds" but still takes real effort and floor space isn't solving the storage problem it's marketed to solve.