When I tore my ACL for the third time this past spring, I figured it was about time to get serious about never ever, ever, ever again sustaining one of these obnoxiously slow-healing and expensive injuries. And because I only want the best for you (and also to make more friends at the gym), I asked my physical therapist, Kim Weichers, DPT, a lifelong skier, to share her best practices for training to prevent alphabet soup of the knees.

First thing is first, skiing is basically one huge test for the ligaments in the knee joint. The leg muscles are constantly lengthening and shortening to absorb the unpredictable dynamic forces coming from all directions, particularly in variable snow conditions. When we land weird or in the backseat, twist backwards or forwards in a fall, or catch an inside edge, our strong muscles are the first line of defense for recovering stable form, but ligaments are the fail-safe for keeping our shit tight and aligned. Cross your fingers like you're making a wish—perhaps to have robot knees—and the ACL is your middle finger. Its main jobs are to help the knee pull back the tibia if it shoots too far forward in relation to the femur, and to prevent excess inward rotation of the tibia.

Most ACL injury prevention programs strengthen neuromuscular response to dynamic loads, aiming to decrease the likelihood that we'll put our ligaments under high-stakes stress. Spoiler alert, this will take some work. Gym time. Like, three sessions a week, ideally. Sorry, not sorry. Just remember: tearing your ACL sidelines you for six to nine months. It's worth it to spend time preventing that. What else were you going to do with your day, shave your mustache?

"It's pre-season, and you're starting to think about getting your ski legs ready," says Weichers, who works at the Whitefish Therapy & Sport Center in Northwest Montana. "Even though you might be really physically fit, you might not be sport-specific ready. Skiing is not a predictable sport. You're not just doing a squat in one perfect, planar motion. Having control over multiple joints, all at one time, in various conditions, it's hard to mimic that. It's really hard to recreate skiing without skiing."

PHOTO: Reuben Krabbe

So, no, you can't do wall sits for days and call it good. A bomber program is going to tick a lot of boxes: strengthening each muscle group, agility, flexibility, balance, and cardio. Here's the good news. Each time you train, just choose a manageable number of exercises from each department, and you might find yourself at the end of the ski season with intact ligaments.

In strength training, there are two main goals. First, eliminate major discrepancies between the same muscle group in each leg. We all have a dominant leg, but Weichers recommends aiming for less than 10 percent strength discrepancy between quads, hams, and glutes. Then, eliminate major discrepancies between muscles groups. There are different strength goals for different muscle groups, which a PT or a trainer can help you identify, but if you're hitting the gym solo, simply work each muscle group to fatigue.

"If someone's quad-dominant, they may think that'll make them a good skier, but without the glutes, hams, calves, and core, the quads are nothing," Weichers says. "I hate training my hamstrings. Why? Probably because they're weak, and that probably puts me more at risk. You have to recognize your biases. If you don't like to train your hamstrings, find a way."

To work the hams, she suggests single-leg pelvic bridge, single-leg deadlifts, Nordic eccentric hamstring curls, or doing hamstring curls while bridging on an exercise ball. At the gym, compare how much weight you can max out on single-leg hamstring curls and seated knee extensions. Are your hammys a little bit—or a lot bit—weaker? Probably. You’re not alone.

PHOTO: Victor Freitas

But you don't have to forsake the quads. To fatigue this muscle group, aim for a combination of closed-chain exercises (where foot is in contact with ground), like single-leg get-ups, step-up/step-downs, or squats, with open-chain exercises (where foot is not in contact with the ground), like hammering the leg extension machine. Stand in front of a mirror to make sure your knee doesn't dip when doing step-up/downs, lunges, squats, et cetera. Also, when the knee is bent forward, it should maintain alignment with the second toe. Proprioception is knowing where your body is in space. Train with good form, and you'll exhibit that form when things get dicey on the hill.

To isolate the gluteus maximus and medius, Weichers recommends side-lying hip abduction, side planks, walking sideways with a band around the ankles or feet, single-leg squats, or single-leg deadlifts. She says that a skier's strength training strategy should absolutely emphasize the glutes, which helps us keep our skis level as we move our legs away from the body's midline. It's especially important for skiers with wider hips—a strong booty helps manage the more offset Q-Angle that the femur takes from the hip socket towards the knee, which frequently contributes to sports injuries in women.

Single-leg calf raises are great for tiring out calves. And, Weichers says, "hammer home the core—if you're sloppy in the core, you can't expect your hip, knee, and ankle to respond how they should down the chain." You know the drill for this muscle group: plank, side plank, and bridge are the trifecta.

For plyometric/agility training, Weichers likes ice skater jumps, 180-degree jump turns, single-leg jumps for distance, and scissor jumps. You don't need to be a yogi, she says, but flexibility is important, too. Work the calves, quads, hammys, hip flexors, hip adductors (butterfly stretch), and hip external rotators/glutes (figure 4 stretch). Challenge your balance by doing single-leg squats on a wobble board or half-dome exercise ball. Definitely don't forget cardio if you want to ski bell to bell—when you're fatigued, you ski sloppy, putting yourself in prime position to blow. And when you finally get out on the mountain, dynamic stretching is most effective pre-sport; static stretching is most effective with an après-beer in hand.

If it sounds like a lot, it's because it is. So is skiing. Go get 'em, tiger.