Leg curls are a resistance training exercise to work certain leg muscles. Find out if that also means they can make your legs bigger.
The leg curl exercise mainly works your hamstring and gastrocnemius calf muscles.
That means leg curls can make your legs bigger in these areas if you do the right amounts of sets and repetitions and use enough weight.
One thing to note is that the gastrocnemius calf muscle is known for being hard to grow. You should mainly expect size increases in your hamstrings aka back thighs.
What do seated and lying leg curls work?
Resistance training exercises typically focus on one or a few muscle groups and seated and lying leg curls are no different.
More specifically, seated and lying leg curls mainly work your hamstring and your gastrocnemius calf muscles.
These are responsible for the typical leg curl motion where you bring your lower leg to your upper leg.
Something to keep in mind is that leg curls do not work your glutes. This is worth noting because the hamstrings help the glutes with hip flexion.
However, the opposite is not the case, your glutes do not help with knee flexion.
Do leg curls work calves?
The big and strong hamstring muscles get most of the attention from people who consider using weight benches with leg curls, leg curl machines, or resistance bands.
However, the same knee flexion movement in the leg curl also works your gastrocnemius calf muscles.
These calf muscles are bi-articular muscles that are attached to your upper leg bone and heel bone.
That means the gastrocnemius calf muscle is involved in both knee flexion (leg curls) and ankle plantar flexion (calf raises).
Do leg curls build muscle in the areas they mainly work?
Just working certain muscles with an exercise is often not enough to cause muscle growth. You also need to approach your training in the right ways to see results.
That means leg curls can help you build muscle in your hamstrings and gastrocnemius calf muscles if you do the right amounts of sets and reps and use the right amounts of weights.
Additionally, you need to give your body enough nutrients and rest to repair and grow these muscles.
One thing to note is that the gastrocnemius muscle is known for being hard to grow.
Your legs will likely mostly get bigger in the back thigh areas by doing leg curls.
Do leg curls make your glutes aka bum bigger?
As mentioned, the knee flexion movement from leg curls does not work your glutes.
That means leg curls will not make your bum bigger no matter how smart you approach the exercise.
Do leg curls increase leg size?
Leg curls can increase your leg size in your back thighs if you do them with the right sets, reps, and weight. Do make sure you give your body enough nutrients and rest too.
Does the leg curl reduce thigh fat?
Working a certain area of your body with resistance training exercises does typically not lead to significant fat loss in that specific area only. That means leg curls generally do not reduce thigh fat. Even so, at a specific point in your weight loss journey exercises like curls could help reduce body fat in this area.