How to Build Your Quads Using Leg Extensions

Nobody wants to be that guy or girl with a big upper body and bird-thin legs. We don’t skip leg day here!

If you’re looking to not only build strength, but build size in your quads, it’s important to know how to target the four individual muscles within the quads in order to:

  • get the look YOU want in your legs

  • target weaker parts of the quads if you favor a certain position when training or in daily life to further improve strength

While there are many techniques to grow our quads, today we’re going to focus on how to utilize the leg extension machine.


But Don’t Leg Extensions SUCK?

While there are some criticisms to using these machines, leg extensions are one of the best at targeting and isolating our quads.

Some of the criticisms that may come up with these machines are that they suck for building muscle and they suck for your knees.

Leg Extensions are Useless for Building Muscle?

This is false. As already stated, when it comes to EMG activity, its been shown to be some of the most beneficial movements to isolate the quads.

The flak you may hear comes into play due to people utilizing machines over compound (multi-joint) movements. For example, if you only do quad extensions, but aren’t utilizing movements such as squat or lunge variations in order to build your quads, its very unlikely you’ll see much progress. This is because there is only a small opportunity for progressive overload (AKA a lack of ability to provide continual, increased stress on the body), which is necessary for muscle growth.

Instead of only using leg extensions, use them as a tool towards the end of your workouts once you’ve already completed your compound movement (such as a squat).


An Example of a GOOD Quad Workout

5x5 Barbell back squats

3x10 Kettlebell goblet squats superset barbell hip thrusts

3x10 Dumbbell Bulgarian split squats (ea)

3x12 Quad extension machine

Why is this a good quad workout? Machines are great as finishers for workouts and work best when placed after our compound movements. All of these movements also target or hit the quads, even if there are other muscles that are being targeted in that movement as well (such as the hip thrusts).


An Example of a POOR Quad Workout

3x12 Quad extensions

3x12 Walking lunges

3x12 Hamstring curls

3x12 Hip abductions machine

Why is this a poor quad workout? There are a few reasons why this workout isn’t the best for building the quads specifically; we want to perform the quad extensions after our main movements, which in this case, it would be the lunges. The second reason this workout wouldn’t be the best is because it focuses the majority of its workout around machines. Remember we can utilize machines to isolate muscles, but we don’t want it to make up the bulk of our workout. The third reason this wouldn’t be the best for targeting our quads is because half of these exercises don’t isolate or target the quads at all. In this, hamstring curls and abductions aren’t necessarily useful for building the quads. To ensure muscle growth in our quads, we want to make sure to keep our training volume relatively high.


Leg Extensions are Bad for Your Knees?

The second issue many have with the leg extension machines are that they’re bad for your knees. While there are some cases where there may be potential risks for injury, most people will not experience issues with this unless they have a history of knee injuries in the past.

To avoid issues with our knees during leg extensions, its important to:

  • avoid going “too heavy” — instead perform with higher rep ranges, for example, 12 reps and using moderate weight

  • avoid using leg extensions as your main muscle-building movement — instead perform the bulk of your workout with movements such as squats and lunges

  • avoid rushing through this workout — instead, make sure to keep reps controlled at a tempo of about 2-1-2-1 (2 seconds descending, 2 second pause at the bottom, 2 second contraction back to the top, and a 1 second pause before beginning the descend again)

  • avoid pain — this is an obvious one, but sometimes it goes ignored regardless, instead, try re-positioning your toes or avoid this movement altogether if you’ve had issues with your knees in the past


Building Your Quads with Leg Extension Machines

Just to reiterate, despite the hate that leg extensions receive, they are one of the best exercises for isolating our quads, which is what you want to hear if you’re looking to build and sculpt your quads. When it comes to this movement, by adjusting the position of our feet, we can target different muscles within our quads to help shape them in the way we prefer.

The biggest areas of focus many aim to achieve in the quads are:

  • Outer sweep

  • The bulk of the quad

  • Tear drop

The Outer Sweep

By pointing the toes in during leg extensions, you shift activation to the vastus lateralis, which focuses on building the outer part of your quad.

The Bulk of the Quad

By pointing the toes out during leg extensions, you put the largest focus in activation on your rectus femoris, which is the bulk of your quad.

The Tear Drop

With what we’ve seen in EMG activity, to build the “tear drop,” the direction in which we position our toes on the quad extension machine has similar activity regardless. This means that you can decide between keeping toes straight ahead, pointing out, or pointing inwards; whichever feels more comfortable to you during the movement.


Final Notes

If you’re looking to build your quads, find a position that is comfortable for you and make sure that you have no current issues with your knees before performing this exercise. We can’t wait to see your progress!

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