Lunges: Benefits, Muscles Worked, and More

Lunges are a classic exercise made popular by both their effectiveness and sheer versatility of purpose.

Whether you’re a calisthenics practitioner stuck at home, a lifter looking to build your quadriceps or an athlete trying to develop lower body coordination, the lunge is the perfect exercise.

In this article, we will delve into the multi-joint and highly dynamic lower body movement that is the lunge - as well as what muscles it works, how best to use it and a few alternatives to try out.

What are Lunges?

Lunges are a highly dynamic compound exercise performed for a variety of different purposes - nearly all of which have to do with strengthening, stabilizing and stretching the lower body.

In practice, lunges are quite simple in execution, as they only require the lifter to take an exaggerated step forwards with each repetition. This makes them a one-sided or “unilateral” movement.

Because lunges are used for such a wide variety of purposes and training methods, programming them can vary quite a bit between different types of athletes.

Bodyweight exercisers may perform lunges unweighted for high volume, and athletes may perform them weighted as part of a training circuit, for example.

What Equipment do Lunges Need?

Traditionally, none.

Lunges can be performed entirely with your own body’s weight.

However, if you’re looking to up the intensity or reach a specific training goal, a pair of dumbbells, kettlebells or weights plates will make loading the exercise far easier.

Who Should Do Lunges?

Lunges are as simple an exercise as they come, and as such are suitable for even complete novices to exercise.

However, balancing properly during a lunge can be difficult for some, and is not recommended for individuals with a history of balance issues - or those that have been deemed a fall risk.

How to do Lunges

In order to perform a repetition of lunges, the lifter should stand upright with their feet set around hip-width apart, core contracted and head facing forwards. If performing the exercise with weights, grip them evenly in both hands.

Now in the correct stance, the lifter will raise one foot and take an exaggerated step forwards, bending at the foreleg’s knee while stretching out the leg behind them as they do so.

Much of the body’s weight should be distributed through the heel of the foreleg, with the hindleg acting in a more supportive capacity.

They will then follow with this downward bend until their forward-facing thigh is parallel to the ground, and the back-knee is nearly touching the floor. Another cue to look for is if both knees are bent at a 90 degree angle. 

Once reaching proper depth, the lifter will will drive through their heel and return to the starting standing position - thereby completing the repetition.

Don’t forget to perform the same movement with the opposite leg as well.

What Muscles are Worked by Lunges?

Lunges are a compound exercise, meaning that more than a single muscle is responsible for completing its movement pattern.

For the sake of specificity, these muscles are divided according to the role they play - for dynamic contraction, the muscle is dubbed a “mover” or “mobilizer, whereas static contraction labels the muscle a “stabilizer”.

Primary and Secondary Mover Muscles

The main muscle used during lunges is the quadriceps femoris, which is responsible for much of the force and movement during the exercise.

Despite the rather vital role the quadriceps play during a lunge repetition, it is further supported by the glutes and hamstrings - the latter less so than the former, as the hamstrings act as dynamic stabilizers.

Stabilizer Muscles

Apart from the mover muscles, lunges also use the calves and the core.

What are the Benefits of Doing Lunges?

Lunges are effective for achieving a wide variety of benefits. We’ve listed the most generally relevant ones below.

Excellent for Building Quadriceps Mass and Strength

First and foremost, the traditional lunge is a quadriceps-dominant exercise. The quadriceps femoris are responsible for knee movement in certain directions - of which are utilized to a full range of motion during a lunge repetition.

This wide range of motion and emphasis on the quadriceps makes the lunge perfect as a tool for building both mass and strength therein.

Of course, this doesn’t mean that lunges don’t work the entirety of the lower body to an effective level, only that it is the quads that benefit the most from this exercise. In addition, the emphasis of the lunge can also depend on the length of the step taken, with wider steps placing more emphasis on the posterior chain.

Highly Functional and Develops Athletic Prowess

The lunge is as functional an exercise as they come, developing not only stability while in a unilateral stance, but also lower body explosiveness, power and strength in a manner that carries over to athletic activities.

Athletes wishing to take full advantage of lunges can perform the exercises as part of a highly dynamic lower body training drill, or otherwise load the exercise in a manner that builds explosiveness.

More Dynamic than Most Split Squat Exercises

Lunges are often confused with split squats, of which are an exercise admittedly quite similar to the lunge in stance and muscular recruitment. However, lunges are far more dynamic, and involve raising the feet off the floor, rather than keeping them in place.

To illustrate, here's a split squat:

This seemingly small difference in movement pattern means that lunges are far more dynamic, making them better at building functional strength and working the leg muscles through a larger range of motion.

Stretches and Strengthens Hip Flexors

Lunges feature a wide stance that place the hips in a state of flexion - meaning that lunges are highly effective for both stretching these muscles, as well as strengthening their main function in a manner that does not overly strain them.

Allows for Greater Focus on One Leg at a Time

Because lunges are a unilateral exercise, lifters do not necessarily need to divide their energy and attention towards both legs simultaneously. 

This is a benefit that is unique to lunges and exercises like it, as it will not only allow for weight to be distributed to one leg at a time, but also aid in fully contracting the muscles of one side of the body with each repetition.

Common Lunge Mistakes to Avoid

Although lunges are quite safe when performed correctly, making the following mistakes could potentially lead to poor training stimulus - or even injury, in more severe cases.

Poor Knee Tracking or Misalignment

The first and most important aspect of the lunge is to optimize the angle of the knees - especially the front-facing knee.

While the general advice is to keep the knee from tracking over the foot, this is not always possible for some individuals. Instead, a better and more widely-applicable cue is to keep the knee aligned with the direction in which the toes are pointing, in terms of both a horizontal and vertical axis.

This means not only keeping the knee at least above the foot, but also to avoid allowing them to collapse inwards or out to the side, as either case can strain the knee joint and disbalance the movement.

Overextending or Underextending the Leg

Although altering the distance of the lunge’s step is a valid way of altering which muscle is worked, a traditional lunge should move the forward leg only enough distance to keep the knees aligned over the foot.

Stepping too far forwards could cause the range of motion to be reduced, impacting the effectiveness of the exercise and leading to poor stability. Likewise, stepping too close turns the exercise into more of a squat, and will recruit certain muscles to a lesser extent as well.

Keep in mind that all lifters vary in terms of mobility and proportions. Experiment to see what stance works best for your own unique physiology.

Dropping the Back Knee to the Floor

Some lifters may make the mistake of lowering so far that their back knee rests atop the ground. 

While this is most often an attempt to maximize range of motion, doing so will distribute the body’s weight into the floor and reduce the resistance placed on the muscles - making the exercise less effective.

In order to ensure that a full time under tension is maintained throughout the lower body’s musculature, it is important for the knees to remain off the ground, with much of the weight resting atop the front leg’s heel.

Hunching the Upper Back, Bending to the Sides or Failing to Stabilize the Torso

Although less likely to result in injury than many other mistakes, poor upper body control during a lunge is a surprisingly common problem.

Misaligning or bending the torso will not only lead to a more difficult time maintaining balance, but could also potentially place more strain on the joints of the legs that is necessary. 

In order to perform lunges correctly, it is important to keep the torso upright with the chest pushed out, the core contracted, and the spine aligned in a neutral manner. This should cover most errors in upper torso position, and aid in distributing the body’s weight through the legs.

Poor Stance Width

Much like under or overextending the legs, the distance between the legs themselves can also be an issue with lunges.

Depending on the lifter’s mobility and proportions, they’ll want to aim for a stance that is just wide enough to allow for a 90 degree bend in both knees simultaneously. Too wide and the position will be difficult to stabilize, whereas too narrow may affect range of motion and further add pressure to the joints.

Like leg extension distance, the lifter will need to experiment to find their ideal stance width as well.

Lunge Alternatives

If the lunge doesn’t quite meet your needs or is too hard to balance - try out an alternative. We’ve listed three substitute exercises below as examples.

Split Squats

Split squats are the more static substitute to the lunge, as they feature a nearly identical stance and muscular recruitment pattern, but do not involve raising the feet off the floor.

The split squat is the ideal alternative for lifters looking to maximize volume or weight lifted despite a less functional training stimulus.

Step-Ups

To take the dynamic aspect of lunges to an even greater level, one can substitute them with step-ups.

As the name implies, step-ups involve the lifter stepping up and off an elevated platform, replicating the general muscular recruitment and movement pattern of lunges but to greater intensity.

Step-ups are ideal for athletes, individuals wishing to increase their caloric expenditure or those who simply wish to take advantage of the benefits seen in dynamic exercise.

Smith Machine Lunges

Although somewhat controversial due to the fixed bar path and disadvantages inherent to the smith machine, the smith machine lunge does serve quite well as a heavier alternative to the standard lunge.

With a greater loading capacity, self-stabilizing resistance and a few additional safety mechanisms, the smith machine lunge can be quite effective as a supplementary lower body exercise - or for those who have trouble maxing out with free weight lunges.

Frequently Asked Questions (FAQ)

What Type of Exercise are Lunges?

Lunges are classified as a unilateral dynamic lower body compound exercise - meaning that it features an uneven stance, an active movement pattern and targets many of the muscles of the legs.

Are Walking Lunges and Lunges Different?

Yes - walking lunges are a separate and more dynamic alternative to the standard lunge. While the regular lunge begins and ends in much the same spot, the walking lunge quite literally involves walking forwards while performing a lunge repetition with each step.

How Many Lunges Should I Do?

The number of lunge repetitions you should do will depend on your goals and training experience. More advanced athletes seeking hypertrophy, strength or endurance can perform as many as 20 repetitions in a single set, whereas newer individuals should aim for somewhere between 6-10 per set.

In Conclusion

The lunge is as effective as it is popular - but remember that it is not as effective at working the posterior chain as some other leg exercises. Keep this in mind, as well as the other limitations that the lunge features.

For a comprehensive and intense workout, we suggest combining lunges with movements like the reverse hack squat, leg curls or deficit reverse lunges as well.

References

1. Boyd, Joni, PhD, CSCS. Milton, Katy, MS. (N.D.) “The Undervalued Lunge” NSCA Personal Trainer Quarterly. Ver 4.4. NSCA.com

2. Bezerra ES, Diefenthaeler F, Nunes JP, Sakugawa RL, Heberle I, Moura BM, Moro ARP, Marcolin G, Paoli A. Influence of Trunk Position during Three Lunge Exercises on Muscular Activation in Trained Women. Int J Exerc Sci. 2021 Apr 1;14(1):202-210. PMID: 34055138; PMCID: PMC8136561.