Which lunge variation is the best?

The answer depends on your strength and conditioning focus and knee joint health.

The primary focus of a lunge is to strengthen the gluteus maximus (your main butt muscle) and the rectus femoris (the central quadriceps muscle at the front of your thigh).

The three most common lunge variations are the reverse lunge, the forward lunge, and the walking lunge. If you have ever attended a class at the gym, followed along to an online video, or worked with a personal trainer you are sure to have experienced at least one of the variations.

So which one gives you the best return for developing muscular strength with the lowest risk of knee joint injury? Biomechanical studies to answer this question are limited. I did come across a small study presented at the 34th International Conference Of Biomechanics in 2016

(https://ojs.ub.uni-konstanz.de/cpa/article/view/6941).

Infrared cameras, force plates, and electromyography were used to measure knee and hip joint moments, knee joint shearing forces, and muscle activation. A joint moment is the measure of the tendency to produce motion about the joint. Knee joint shearing forces are opposing forces that push parts of the knee joint in opposite directions - ouch! Muscle activation is a measure of how strongly the muscle contracts. The study concluded that the reverse lunge gave the best muscle activation - thumbs up for strength building! Whilst causing the lowest momentary shearing forces at the knee joint - double thumbs up for pain-free knees! However, this study used only four participants, with no orthopaedic medical conditions of the knee. All four participants were fitness professionals. Thus we can assume they utilised a perfect technique in all three lunge exercises. Imperfect technique and/or orthopaedic conditions of the knee joint would drastically affect the biomechanical data recorded and potentially the study conclusions.

Okay so it seems that the reverse lunge gives you the biggest bang for your exercise time. Provided you have no pre-existing knee conditions. Where does that leave those of us who, like me, have shall we say “challenged” knees?

A 2015 study published in the Journal Of Athletic Training sought to answer this question. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4641539/).

The biomechanics of the forward lunge, the reverse lunge, and the single-leg squat were analysed from a rehabilitation perspective. We will not discuss the single-leg squat here as it falls outside of our lunge based question.

If you have knee joint degeneration such as osteoarthritis (three cheers for the creaky knee crew!) the study concludes that the reverse lunge is the best choice. Lower joint compressive load and shear forces were recorded on the knee joint when compared to the forward lunge. Thus, reducing the risk of further joint damage.

However, this is not necessarily true if your knee issue is due to a soft tissue injury. In this case, you want to progressively stress the soft tissues to prevent the formation of disorganised scar tissue that is structurally weaker. A progressive program with the forward lunge would be the best exercise in this scenario due to the production of a higher knee extension moment (thus more stress on the soft tissues around the knee) than the reverse lunge. Okay, I hear you say but why not the walking lunge as it is just a series of forward lunges? Surely that would be the most effective option? Not if you are in the initial stages of rehabilitation. In the initial stages additional physical support is likely to be needed. It is easier to control this physical support for a single forward lunge. However, the end phase of recovery should see a progression to walking lunges.

And there you have it. All three lunge exercises have a purpose. Just choose the lunge that suits your knee health best.

Stay informed and enjoy your fitness training :-)