Hamstring Curl: Benefits, Daily Life Uses and How to Start
The hamstring curl is an exercise where you bend your knee against resistance, pulling your heel towards your bottom, and it is a must because it directly strengthens the hamstrings, which protect your knees and power your running stride. Most people's daily lives involve a lot of sitting and very little hamstring work. A few sets of curls each week is a simple way to fill that gap.
Why the hamstring curl is a must
Your hamstrings are the three muscles running down the back of your thigh. They have two jobs: extending the hip (as in a deadlift) and bending the knee. Hinge exercises mainly train the first job. The hamstring curl trains the second, knee flexion, which many programmes miss.
It mainly works:
Hamstrings: especially the lower part near the knee.
Calves: the gastrocnemius helps bend the knee too.
Because curls isolate the muscle with little load on your spine, they are a useful addition for people who want stronger legs without more heavy lifting. Combined with a hinge such as the Romanian deadlift, they cover both roles of the hamstrings.
How it helps in everyday life
Walking and running: the hamstrings slow your lower leg as it swings forward, so they work hard in every stride, especially when you speed up.
Stairs and hills: they help stabilise your knee as you climb and descend.
Sport: sprinting, football, tennis and five-a-side all place big demands on the hamstrings.
Knee control: hamstrings work alongside the quads to keep the knee steady when you land, turn or change direction.
Balanced legs: if you do lots of squats or cycling, curls help balance out quad-dominant training.
What it can help prevent
Research and coaching practice suggest regular hamstring strengthening can help with:
Hamstring strains: stronger hamstrings, particularly when trained through a full range, are linked with a lower risk of strains in running sports.
Knee niggles: strong hamstrings support the knee joint and help share the load with the quads.
Muscle loss with age: resistance training of all major muscle groups helps maintain muscle as we get older, in line with NHS advice to do strengthening activities at least 2 days a week.
Imbalance from sitting: long days at a desk leave the back of the legs underused; curls give them direct work.
For a more advanced hamstring exercise with good evidence behind it in sport, see the Nordic curl.
Who it suits (and who should be careful)
Hamstring curls suit beginners, older adults, runners and anyone returning to training, because the movement is simple and the load is easy to control on a machine or with a band.
Be careful if you have a current hamstring tear, recent knee surgery or cramping in the back of the thigh. Start light, as hamstrings can cramp when they are not used to direct work. If you are recovering from an injury or have ongoing pain, speak to your GP or a physio first.
How to start safely
Set up the machine: line your knee up with the machine's pivot point and the pad just above your heels.
Control both ways: curl smoothly, squeeze for a second, then take two to three seconds to lower.
Keep hips down: avoid lifting your hips or arching your back to finish the rep.
Use full range: straighten the leg fully at the bottom without slamming the weight.
Start here: 2 to 3 sets of 10 to 12 reps, twice a week, at a weight that leaves two or three reps in reserve.
Easier version: a resistance band curl lying face down, or a stability ball hamstring curl with both legs. Harder version: single-leg machine curls or single-leg ball curls.
If knee health is your main goal, my knee strengthening exercises guide shows how curls fit with other moves.
FAQs
Are hamstring curls good for your knees?
For most people they are, because strong hamstrings help support and stabilise the knee. If you already have knee pain, get it checked by a GP or physio before adding load.
Seated or lying hamstring curl, which is better?
Both work well. Research suggests the seated version may have an edge for muscle growth because the hamstrings work in a more stretched position, but the best one is the one you can do comfortably and consistently.
Do I need hamstring curls if I already deadlift?
Deadlifts train the hamstrings at the hip, while curls train them at the knee, so doing both gives more complete hamstring strength.
If you want this coached 1-to-1, my 12-week body transformation in Archway builds exercises like the hamstring curl into a plan around your body and goals, or see my personal training prices.
