12 % incline · 3 mph · 30 min

12-3-30 Calories Burned at 120 lb

A 120 lb (54 kg) person burns about 236 calories doing the 12-3-30 treadmill workout — roughly 2.5× as many as 30 minutes of flat walking.

12-3-30 (gross)
236
kcal in 30 min
Net (above rest)
208
kcal
Flat 3 mph walk
94
kcal in 30 min
Per hour at 12 %
472
kcal

Use your own numbers: open the 12-3-30 calories calculator →

30-minute calories at 120 lb by incline and speed

Incline2.5 mph3.0 mph3.5 mph4.0 mph
0 %8394105116
3 %113130147163
6 %142165188211
9 %172201229258
12 %202236271305
15 %231272312353

ACSM walking equation: VO2 = 0.1·S + 1.8·S·G + 3.5 (S in m/min, G as a fraction); kcal ≈ VO2 × kg ÷ 1000 × 5 per minute. Valid for walking speeds of roughly 1.9–3.7 mph; values at 4.0 mph are an extrapolation.

Is 12-3-30 a good workout?

It is a demanding but low-impact cardio session: at 12 % incline the energy cost of walking at 3 mph is similar to running at roughly 4.5–5 mph on the flat. Steep incline walking loads the calves and Achilles, so build up the incline and duration gradually and avoid holding the handrails, which reduces the work.

Other body weights

Try any speed and incline with the incline walking calculator, or compare with a treadmill running session.

Last reviewed: October 2026 · Health disclaimer

FAQ

12-3-30 at 120 lb: questions

About 236 kcal in 30 minutes (gross) for a 120 lb (54 kg) person, using the ACSM walking equation at 12 % incline and 3 mph. That is about 208 kcal above resting.

Walking 30 minutes at 3 mph on the flat burns about 94 kcal at 120 lb, so the 12 % incline roughly 2.5× the energy cost.