Enter your machine weight and total reps to calculate your calories burned doing leg extensions. At a standard 18-inch range of motion, 100 lb burns about 0.27 calories per rep, or about 2.68 calories for 10 reps.

Leg Extension Calorie Calculator

Basic
Advanced

Basic uses a standard 18-inch movement path. Advanced lets you enter a custom range of motion.

Leg Extension Calories Burned Formula

The basic calculator uses a standard 18-inch movement path for each rep.

C = W × R × 0.00268

The advanced calculator adjusts for a custom range of motion.

C = W × R × D × 0.00179
  • C = calories burned
  • W = loaded machine weight in pounds
  • R = total reps
  • D = one-way movement distance in feet

Example: 100 lb × 10 reps × 0.00268 = 2.68 calories.

Leg Extension Calories Per 10 Reps

Loaded WeightCalories for 10 RepsCalories per Rep
50 lb1.340.13
100 lb2.680.27
150 lb4.020.40
200 lb5.360.54

What Is a Leg Extension?

The leg extension is a machine-based isolation exercise that trains knee extension. It primarily targets the quadriceps, especially the rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius.

Leg Extension Quick Facts

  • Main muscle group: quadriceps
  • Primary joint action: knee extension
  • Common training ranges: 10 to 15 reps for moderate sets, 15 to 20 reps for lighter burn sets
  • Higher load, more reps, and longer movement distance all raise calories burned
  • Basic mode is best for quick set logging on standard selectorized machines

How to Use the Calculator

  • Select Basic for a standard 18-inch movement path.
  • Enter the loaded machine weight and your total reps.
  • Select Advanced if you want to enter a custom range of motion.