If you want strong legs, it goes without saying that you can’t skip leg day. But what if you hit legs religiously every week and you still can’t gain strength in the lower body?

Here are five big mistakes people make when trying to achieve strong legs

Avoiding the Squat

The most obvious reason your legs aren’t strong is that you don’t squat. Now, I understand some people have injuries that don’t allow them to squat, these people get a pass. But if you are healthy and free of injury, get your butt in the squat rack! There is no substitute for barbell back squats. Leg presses, Smith Machine squats, and leg curls all have their place, but the benefits of these exercises pale in comparison to a properly executed squat.

Not Squatting with Full Range of Motion

If you are squatting, that’s great. But are you squatting with a full range of motion? By full squats, I am referring to a below parallel position (hip crease below top of patella). Full squats have been proven to be superior for strength and muscle building when compared to their half squat counterpart.

Are full squats bad for your knees? No, according to the science, they are not. Full squats actually help strengthen the structures of the knee and aid in injury prevention.

Doing Long, Slow Cardio

Not all cardio is created equal. If you are slogging away for hours jogging or walking on a treadmill you may actually be hurting your strength gains. One study found that combined strength and endurance training can suppress some of the adaptations to strength training. So, how do you get your cardio in without hurting strength gains? The answer lies in high intensity interval training, or HIIT. HIIT can give you a superior cardiovascular workout while preserving muscle mass and strength.

ot Progressively Overloading

When you impose stress on your body your body will adapt and change to better handle that stress in the future. So, if you go in to the gym and do 4 sets of 10 every week with the same weight your body will adapt to that stress. But the whole point of lifting is to continue progressing. That means that once your body adapts to 4 sets of 10 you have to change the stressor. This can be adding more reps, more sets, more weight, or cutting down rest periods.

Not Enough Protein

Nutrition is a very broad topic, much too broad for the scope of this article. So, I am going to focus on one of the most important macronutrients you need to build strength; protein. The guidelines for protein consumption I will lay out are not for the casual exerciser or the normal “Joe Blow” on the streets. These values are for the people who are serious about gaining strength. For the intense strength athlete, at least 1g of protein per pound of bodyweight is needed to facilitate the muscle adaptation process.