As their name implies, leg extensions involve using at least some parts of your legs. Find out if this is enough to actually build bigger legs.
Leg extensions are a resistance training exercise that focuses on your quadriceps aka your front thigh muscles.
That means you can build bigger legs, more specifically bigger front thighs, with a leg extension machine if you implement the right weight, repetition ranges, nutrition, and rest time.
One important thing to note is that leg extensions do not do anything for other leg muscles like your glutes (butt), hamstrings (back thighs), hip adductors (inner thighs), hip abductors (outer thighs), and calves.
To grow these areas of your legs and avoid muscle imbalances, you have to work these muscles with other exercises.
Do leg extensions make your thighs bigger?
To make your thighs bigger in a healthy way, you have to grow the muscles in this area.
These muscles include the quadriceps (front thighs), hamstrings (back thighs), hip adductors (inner thighs), and hip abductors (outer thighs).
To grow these, you have to put them under enough pressure, do enough repetitions, give your body enough nutrients, and give your body enough rest.
Leg extensions are a quadricep resistance training isolation exercise.
In simpler words, that means leg extensions can make your front thighs bigger if you do them with the right weight and repetitions.
Leg extensions can definitely help you build big quads without doing any squats (although this is generally not recommended).
At the same time, you need to keep in mind that leg extensions will have no impact on the other parts (back, inner, outer) of your thighs. To make these areas bigger, you will have to turn to other exercises.
Should you go heavy on leg extensions?
How heavy you should go on leg extensions depends on your training goals, the rest of your workout routine, and your body.
That being said, to grow your quadriceps, you generally want to go with a weight where you can barely complete 6 to 20 repetitions.
You could go even lighter than that, do higher repetition ranges, and still see great results but most people will prefer the feeling of more medium rep ranges.
Partly due to the muscle fatigue you experience and partly due to how out of breath you get from exercises like leg extensions that work bigger muscle groups.
Can you do leg extensions every day?
Something important to note is that just because a resistance training exercise can help you grow and strengthen certain muscles does not mean you should do it every day.
While doing leg extensions you damage your quadricep muscles. This may sound bad but actually starts a variety of internal processes that can grow and strengthen them over time.
However, your body still needs time (and nutrients) to complete these processes. Especially for bigger muscles like the quads.
If you work the quadriceps before they had time to repair and grow, you will actually reduce the results you get from leg extensions.
Exactly how often you should do leg extensions depends on your training goals, body, repetition ranges, and the rest of your workout plan.
That being said, most people want to implement at least one rest day in between their quad workouts. You generally don’t want to do leg extensions every day.
Are squats and leg extensions enough?
Squats are another very popular and effective exercise. It mainly works your quadriceps but also engages your glutes, hamstrings, and lower back muscles a nice amount.
So a good workout program with squats and leg extensions is enough to grow and strengthen your quadricep muscles.
However, only doing these two exercises will not be enough to call your leg workout program good.
You also want to implement exercises like deadlifts and/or good mornings that focus on the glutes and hamstrings to have a balanced muscle size and strength distribution.
Additionally, you could also consider implementing hip adductions and hip abductions to focus more on the inner and outer thigh muscles.
How to work different parts of your quads with leg extensions
Your quadriceps are actually a muscle group that consists of 4 main other muscles.
Interestingly enough, you can influence in what ratio these 4 quadricep muscles are worked by changing the angle of your feet while using a leg extension on a weight bench or the dedicated machine.
By pointing your feet inward during leg extensions, you will focus more on the vastus lateralis aka the outer quadricep muscle.
On the other hand, by pointing your feet outward during leg extensions, you will focus more on the rectus femoris aka the middle/front quadricep muscle.
Most people will not care too much about these differences. In that case, doing the exercise in the most comfortable position and/or just forward is generally a good choice.
That being said, bodybuilders and people trying to improve performance in certain movements can consider doing their leg extensions in a certain way.
Do leg extensions make your thighs smaller?
No, unless they help you lose body fat in this area, leg extensions do not make your thighs smaller. In fact, they do the opposite. Leg extensions make your thighs and more specifically your quadriceps aka quads bigger.
Do leg curls make your legs bigger?
Leg curls, the opposite of leg extensions, can make a certain part, more specifically your hamstrings aka back thighs, bigger by growing these muscles.
