I’ve begun training for a half marathon, and within the first few weeks, my knees started to hurt. It wasn’t surprising – that tends to happen when I begin a new exercise routine or when I have a particularly tough workout. There is added pressure on that area, because the knees bear the weight of your body when muscles aren’t used to being challenged.

But sometimes, knee pain can make us avoid working out altogether – lapsing into our old habits of sitting and lying down, as opposed to keeping our bodies moving. As many recent studies have shown, sitting can be as bad for the body as smoking, so it’s important to keep it moving. So what do you do?

For one thing, you can try other types of exercise that take weight bearing off the joints, like swimming. Swimming is a great cardio workout and very easy on the joints. However, as most doctors will tell you, you must incorporate some weight-bearing and strengthening exercises into your routine, especially as you get older, to help keep your bones strong, avoid arthritis, and keep your muscles engaged.

When my knees began to hurt, I didn’t want to ignore the pain, and I didn’t want to back out of my training program. After all, running has helped me with weight loss, toning and defining muscles, and it also has a side benefit of lifting my spirits each day before I head in to the office (to sit in front of a computer for eight hours, which isn’t so healthy).

When I reached out to a physical therapist, he asked me to do some basic squats along with some leg exercises, to see what was happening. As it turns out, my knee pain is a direct result of the lack of strength in my glutes, (a.k.a my butt).

The problem? Sitting. Think about your own schedule – do you spend more than an hour a day in the car, commuting to and from work? Do you sit in front of a computer? A TV? Chances are, this has impacted your posture, and has de-activated your glutes.

The solution is to fire up the glutes again, with exercises that work out these muscles. For some simple exercises you can do at home before you begin any workout routine, try these: 4 Simple Exercises to Get Your Glutes Fired Up. Also, it’s important to stretch your hips before and after a workout, to ensure those activated glutes release the acid build-up from exercise.

When you incorporate some strength training into your exercise routine, you start to see results, not only with endurance during workouts, but also with areas that tend to get inflamed, like the knees. Stop putting all the pressure on your knees and build up your hip and glute muscles, which can handle the heavy lifting. Then you are on your way to a healthier (and happier) workout.