Hamstrings
Natural Leg Curl
The Natural Leg Curl is a strength exercise with no equipment for your hamstrings. Share of the load in the Zulta muscle model: hamstrings (semitendinosus/-membranosus) 44%, hamstrings (biceps femoris) 30% and calves (gastrocnemius) 10%.
How to do it
- Kneel on a pad and anchor your ankles under a fixed bar, a loaded barbell or a partner's hands.
- Start upright with hips extended and arms crossed or held in front of the chest.
- Lean forward slowly by straightening the knees while keeping a straight line from knees to head.
- Lower until you can no longer control the descent, then catch yourself with the hands.
- Push off lightly and curl the body back up with the hamstrings to upright.
Tips
- Keep the glutes squeezed so the movement stays at the knees.
- Build range week by week rather than dropping into the bottom.
Common mistakes
- Folding at the hips to make the lever shorter.
- Letting the ankles lift out of the anchor.
- Using a big push from the hands to get back up.
Muscles worked by the Natural Leg Curl
Share per muscle in the Zulta muscle model. The model spreads the load of one rep over 40 muscles, based on EMG and biomechanics research.
The body lowered against the hamstrings; Nordics bias semitendinosus (Bourne 2017). Knee flexion with the thigh fixed isolates the hamstrings, with gastrocnemius assisting; a flexed hip (seated) lengthens the hamstrings and grew them more than lying curls.
Natural Leg Curl alternatives
Same equipment
Different equipment
Easier
Make it easier
Similar exercises
Frequently asked questions
What muscles does the Natural Leg Curl work?
Mainly the hamstrings (semitendinosus/-membranosus) and hamstrings (biceps femoris). The calves (gastrocnemius) assist.
Is the Natural Leg Curl good for beginners?
The Natural Leg Curl is rated advanced. If you are new, learn the Banded Nordic Curl first and build up from there.
What is a good alternative to the Natural Leg Curl?
For example the Banded Nordic Curl, Glute Ham Developer Raise and Nordic Curl. They train mostly the same muscles, some with different equipment.
Sources
- Maeo et al. 2021, MSSE 53(4):825-837 (seated vs prone leg curl)
- Bourne et al. 2017, Br J Sports Med 51(13):1021-1028 (Nordic curl biases semitendinosus)
Log your sets in Zulta
Zulta tracks your sets, weights and muscle load next to your running, riding or Hyrox training. The app opens soon.