Leg Extension: Are you kicking your legs up with momentum?
Straighten your knees at a controlled pace to lift. Do not kick up using momentum.
How to fix it
- Align your knees with the machine's pivot and place the pad against your shins just above your ankles.
- Straighten your knees to lift the pad without momentum.
- Slowly lower back to the starting position.
The app sets the reps for your next set
(For exercises you added to your routine yourself) For example, if you are a beginner and completed all 13 reps in each set at 30kg as planned in your last workout, the app keeps the weight the same and increases your reps to 14. When you log your sets, GYMKC reads your last set and recalculates the weight and reps for your next set.
Get GYMKC on the App StoreShould you straighten your legs all the way?
Sources differ slightly. Some suggest lifting until your legs are straight. Others suggest lifting only until your knees are almost straight, without locking them. Either way, lift without momentum.
See this exercise in detail
More on the same body part
Sources
- NSCA, Basics of Strength and Conditioning
- ACSM, Position Stand · Progression Models in Resistance Training for Healthy Adults
- Plotkin D et al., PeerJ (2022)
- Azevedo PHSM et al., Biology of Sport (2022)
- Cheon S et al., International Journal of Environmental Research and Public Health (2020)
- Jessee MB et al., Frontiers in Physiology (2018)
- ExRx.net, Lever Leg Extension
- Mayo Clinic, Knee extension with weight machine
- Mayo Clinic, Weight training: Do's and don'ts of proper technique
This article is based on our analysis of public content from evidence-based training experts in Korea and abroad. It is not a substitute for medical advice.