Unilateral exercises are great and extremely important to work into your program when training. Not saying bilateral exercises aren’t, but single leg ones are usually more neglected.
Here are some reasons why…
Improving Sports Performance and “Functional” or “Sports Specific” Training
Pretty much every sport will require you to be on or use just one leg at one point or another. Running is single leg stance activity, basketball players making lay ups, volleyball players running slides or landing, baseball players pushing off the mound, the list goes on and on.
There’s probably others, but the only sport I can think of that don't are rowing, powerlifting, and olympic weightlifting. Read more to see how even with those sports single leg work is beneficial.
With that said though, it would make sense that you would want to train and implement single leg exercises and activities into your program.
Variability Into Programming
Are you hitting PLATwith your training? Are you doing the same exercises over and over? Adding variations and variability into your program can help. Now it can come in many different forms, stance variations (i.e. sumo deadlift, conventional, snatch grip, etc), type of contraction (isometric, concentric, eccentric), tempo, and yes SINGLE LEG
Less Spinal Loading
With single leg exercises, you can get similar amount of muscle activation and loading as that of bilateral exercises, without as much load on to the spine at one time.
Injury Prevention and Addressing Imbalances
Let’s take an ACL injury for example. Many times this occurs without contact, a non contact injury. It happens commonly when athletes are cutting (football), have their leg planted (soccer), are jumping or landing (volleyball and basketball), and other movements. Why is this happening even if they’re not being hit?
Muscle imbalances, like quad to hamstring ratios of the same leg are shown to be a risk factor for injuries. Asymmetries from leg to leg in strength, stability, and control are also shown to be risk factors for injuries.
Single leg work allows you address any muscle imbalances and asymmetries you may have.
Implementing single leg work to address and improve on these asymmetries is crucial if you want to reduce your risk of getting hurt.
Here are a few single leg exercises that I think should be included into your programming...
1) 3 Way Slider Lunge
2) SL RDL
3) Rear Foot Elevated Split Squat
4) Single Leg Hip Thrust
5) Lateral Step Up
6) Anterior Step Up