LifeSpan TR5500iM Folding Treadmill
A 4.0 HP folding treadmill with a 22 by 60 inch belt and two decline levels — the running one that still folds.
Specs
| Drive motor | 4.0 HP continuous duty DC |
|---|---|
| Belt size | 22 in W x 60 in L |
| Belt type | 2.2 mm thick |
| Speed | 0.5 to 13.5 mph |
| Incline | 13 levels of incline, 2 levels of decline |
| Incline motor | 800 lb maximum lift |
| Rollers | 2.5 in front, 2 in rear |
| Deck | 1 in phenolic |
| Deck suspension | 8 independent compression shocks |
| Dimensions unfolded | 73 in L x 34.5 in W x 55.5 in H |
| Dimensions folded | 40.5 in L x 34.5 in W x 65.5 in H |
| Step-up height | 9 in |
| Max user weight | 350 lb |
| Power | 115V NEMA 5-15 non-GFI circuit |
| Warranty | 10 years frame, 2 years parts, 1 year labour |
These figures are copied from LifeSpan Fitness’s own published specs and were last checked on 2026-08-31. Manufacturers revise products without notice, and variants differ. Confirm anything your decision depends on with LifeSpan Fitness before you buy.
Choose this one if
- You actually run, rather than walk fast
- You want decline as well as incline
- You want a running deck that still folds away
The detail
Twenty-two by sixty inches is the belt size that makes a treadmill runnable. LifeSpan's TR1200i and TR3000i both use 20 by 56, which is a walking deck — a running stride overshoots it and you spend the session watching your feet. This is the model where that changes, and it is the single most important difference in the range.
Four horsepower continuous duty backs it up. Continuous duty is the sustained figure rather than a peak, and 4.0 HP is enough to hold 13.5 mph under a heavy runner without the motor labouring — which is what kills treadmill motors.
Two levels of decline is unusual and genuinely useful. Downhill running loads the quads eccentrically in a way nothing else on a treadmill does, and it is specific training for anyone racing on hilly courses. Most home treadmills only go up.
Thirteen incline levels on an 800 lb lift motor covers the uphill side.
A 1-inch phenolic deck on eight independent compression shocks is the same suspension as the TR3000i, and it is what makes a running treadmill tolerable over years.
It still folds, which for a running-capable treadmill is the trick: 73 inches of floor becomes 40.5, standing 65.5 inches tall. The TR6000i is the non-folding sibling with an AC motor.
Ten years on the frame, 2 years parts, 1 year labour. Requires a 115V non-GFI circuit — a GFI outlet will trip.
LifeSpan does not publish the product weight for this model, which for something you intend to fold is worth asking about; the comparable TR4000i is 239.5 lb.