Looking to build legs the size of tree trunks? While the traditional barbell back squat is a staple for almost any lower-body routine, single-leg variations are a great way to improve your workout and add a new element of intensity to spur huge gains.

Unlike traditional moves like back squats and deadlifts, single-leg variations put much less compression and tension on the spine—making them ideal for those that tend to develop frequent back issues.

They also offer the added benefit of balance, stability, and core control. That translates to more work for your midsection.

While they do offer a stability challenge, one-leg variations are far from easy and still offer a tremendous stimulus for muscle growth.

The key here is balance—and if you’ve gotten accustomed to performing traditional lifts, you may need to start out lighter and work your way up as you get your bearings.

By working one side at a time, you’ll also be able to uncover strength differences from side to side. Evening out your leg strength translates to stronger lifts when you return to the rack. 

Try integrating the following three unilateral exercises into your routine in place of their double-leg counterparts.