Whether you want to work towards the coveted Dorito shape (yes, that’s a thing), size up your T-shirts (or make your current ones more snug), or make your waist look smaller, your plan of action should include strengthening your lats. 

The main movers in your back, your latissimus dorsi muscles (or lats) are the broad, sail-shaped muscles that sit just below each of your shoulder blades. These muscles extend down your back, run along several of your vertebrae, and extend all the way down to your pelvis, explains certified strength and conditioning coach Jake Harcoff, C.S.C.S., owner of AIM Athletic. “Well-developed lats create the V-taper physique many people are after while also adding width and thickness to the back,” he explains. Basically, if you want to look jacked, the lats are where it’s at.

So, how do you develop strong, capable lats? Ahead, why these muscles are important, plus five rules to keep in mind if you’re looking to build a massive back. 

Strong Lats Offer Benefits Beyond Physique

Your lats aren’t just vanity muscles; they’re functional muscles, too. At the most foundational level, your lats help you maintain proper spinal alignment, support healthy shoulder positioning, and help you move your arms, says Harcoff. When strong, your lats help pull your shoulders back to improve posture, so you can stand tall and proud.

Read More: 5 Exercises That’ll Help Improve Your Posture

Strong lats also improve overall upper body strength, increase your pulling capacity, and help you twist safely, Harcoff notes. Indeed, these muscles come in handy when you pop up and over a pool’s edge, haul a package off the porch, or even open a door. “The lats also transmit force produced from the lower body to the upper body,” he explains. “When athletes can throw balls or swing objects with great velocity, they typically have strong lats.” 

5 Ways To Maximize Lat Gains

Clearly, your lats do more than make you look massive; they also unlock whole new levels of upper-body strength. Get the most lat gains out of your workouts by making these key workout tweaks.

1. First, Activate Your Lats

Chances are, you’re already implementing exercises widely praised for their ability to strengthen your lats—like pullups, rows, and pulldowns—but if you are not actually using your lats during those exercises (which is more common than you think), they won’t get stronger. “It is possible for people to use their shoulders, biceps, and smaller, surrounding muscles to do more of the work of these movements than intended,” explains physical therapist Grayson Wickham, D.P.T., C.S.C.S., founder of digital movement platform Movement Vault. While this will help those other muscles get stronger, it won’t result in your lats getting strong as efficiently as possible. Plus, if you’re not using your lats for movements that should be lat-dominant, you risk overuse injuries in the muscles that end up taking on the load.

To keep this from happening to you, start by learning how to consciously activate your lat muscles without weight, says Wickham. “If you can put your brain and concentration into flexing your lat muscles outside of exercise, then you’re more apt to be able to activate them during exercise,” he explains. To flex your lats, keep your elbows tucked in towards your ribcage and think about squeezing lemon under your armpits. (“If your elbows start to flare away from your body while you do this, you’ll end up activating your rhomboid and rotator cuff rather than lats,” Wickham notes. So keep those elbows in tight!

From there, you’ll want to try to duplicate that same muscle contraction and feeling during your exercises, says Wickham. Before jumping into your working sets, do a set dedicated to muscle activation, either with lower weights than usual or with an easier variation of that particular exercise. This ensures you can engage your lats while under tension.

If you have a hard time activating your lats with muscle-mind connection alone, Wickham recommends having someone—ideally a trainer—place a hand on your lat before or during a movement. “Sometimes the tactile cue can help people more easily activate their lats in order to lift properly,” he says.  

2. Implement The Progressive Overload Principle 

If you’ve hit a strength or size plateau with your lats, odds are you are not sufficiently challenging them. Consider this: Are you doing the same reps, sets, and weights that you were doing a few weeks ago? If so, it’s time to edit one or more of those variables. 

Making consistent strength and conditioning gains requires that you employ the progressive overload principle, which states that in order for an exercise program to effectively stimulate muscle growth, it has to continuously challenge your muscles, says Harcoff. The body is smart and adapts to whatever you throw at it, so you have to up the ante in order for it to continue adapting (a.k.a. get stronger), he explains. 

Read More: 6 Signs Your Workout Routine Isn’t Working For You

As far as your lats are considered, “that means you need to continue to progress the load applied to your lats in order to continue improving their size and strength,” says Harcoff. There are a variety of ways you can do that, including doing more reps per set, increasing the number of sets you do, cutting down on rest between sets, and slowing down the tempo of your reps. “However you implement the principle, when you subject your lats to greater demand, you promote muscle hypertrophy,” he says. 

3. Make Sure You’re Lifting Heavy 

How you approach lifting depends on your goals—and if you want to build size and strength in your lats ASAP, you need to lift heavy, says Wickham.

Exactly what qualifies as heavy depends on how strong you are and your current one-rep max. But ideally, you want to make sure at least one of your upper-body days involves lifting in the four to six-rep range, says Wickham. The weight you choose for these reps should be heavy enough that you couldn’t complete two more reps with it. (This is known as training to fatigue). 

According to Wickham, it’s common for people to shy away from using heavy weights for lat exercises because they are part of the upper body. However, your big back muscles can probably handle more weight than you give them credit for. “The lats are one of the biggest muscle groups in the body, so they can handle heavier weights,” he says. As long as you’re lifting with sound form, don’t be afraid to pile on the weight. 

4. Don’t Rely Too Much On Cables

If you belong to a big box gym, you probably have access to cable machines galore. No doubt, when used for rows and pull-downs, cable machines can help you bulk up your back. “Cable machines allow you to maintain tension throughout the entirety of each rep, which results in significant time under tension,” Harcoff explains. Plus, you can also use them to isolate your lats, which is helpful when your core is tapped out from your previous workouts or your shoulder stabilizer muscles are toast from push day. 

However, if you forgo free weights in favor of the cable machine every single back day, you leave lat gain opportunities on the table. “Free-weight exercises require greater stabilization to perform, and therefore require you to engage more muscle fibers in the lats and surrounding muscles to help you control the movement,” says Harcoff. Greater muscle fiber recruitment means greater muscle breakdown, which then translates to greater muscle growth following repair—and that’s what you want here! 

Read More: How To Get Past A Muscle-Building Plateau

Additionally, free-weight rowing and pulling exercises allow you to access a greater range of motion than cable variations since the weight isn’t attached to a fixed stand, says Wickham. A greater range of motion also contributes to greater strength gains, so swapping out the cables will serve you well.

5. Add In Some Unilateral Accessory Work Exercises

“If you want to get big, loading the system as much as possible is going to give you the best results,” says Wickham. As far as your lats are concerned, that means doing bilateral, high-demand exercises like the barbell row and pullup, in which your body has to really max out its efforts. 

However, that doesn’t mean you should forgo unilateral lat exercises like single-arm pulldowns or rows, according to Wickham. Actually, incorporating unilateral pulling exercises into your routine is a great way to fix any imbalances between your right and left lats, he says. You see, when you do one-sided pulling exercises, your stronger side cannot compensate for your slightly less-strong side. Long term, this helps reduce your risk of injury on the weaker side, enabling you to keep getting bigger and bigger, stronger and stronger without hitting any roadblocks. 

Your move: Add in a circuit of unilateral lat exercises (such as the dumbbell row, dumbbell snatch pull, and single-arm cable row) to the end of your back day routine, suggests Wickham.