The Strength-Training Hack That Will Dramatically Improve Your Lifts

Ever notice how much more difficult it is to perform a biceps curl or squat at a slower, more controlled pace? It may be easier to just swing a weight up, but it means you're missing out on a lot of the strength-building benefits the exercise has to offer.

Muscle contraction and your mind-muscle connection work hand-in-hand in the weight room. It may seem insignificant but slowing down, visualizing your exercises and squeezing your muscles may have more of an effect on your strength than you think.

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When you stretch your legs and feel a squeeze on your quads or flex your biceps for a photo, your muscles are performing a contraction. Muscle contractions happen in one of three ways: concentric, eccentric or isometric.

When your muscles shorten, it's a concentric contraction, and when they lengthen, it's an eccentric contraction, according to the American Council on Exercise. Isometric contractions occur when your muscle contracts and actively holds, meaning there's no change in muscle length, according to the National Academy of Sports Medicine.

To better understand muscle contraction, imagine a biceps curl: As you pull the dumbbell toward the biceps, the muscle shortens, which is concentric. If you hold here for a moment, the muscle is being held isometrically. Then, as you extend the weight away from your bicep, the muscle lengthens and contracts eccentrically.

The reason muscle contraction matters is related to your increase in strength. All three forms of muscle contraction play a role in increasing your strength and size. That means squeezing your muscle during your exercises can help increase your muscle fiber recruitment, ultimately increasing your strength, says Mathew Forzaglia, certified personal trainer and founder of Forzag Fitness on the NEOU App.

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Simply put, the mind-muscle connection involves visualizing the muscle you're working in order to increase muscle activation and blood flow, according to the American Council on Exercise.

Yes, simply thinking about the muscle you're training can help increase muscle strength and size. After 29 research participants had their wrists wrapped (and therefore weakened) for four weeks, half were instructed to actively visualize flexing their immobile wrist for 11 minutes a day, five times a week. The December 2014 study published in the Journal of Neurophysiology found that wrist muscles in participants that practiced visualization were two times stronger than those that did no visualization.

A similar March 2016 study published in the European Journal of Applied Physiology found that focusing on the muscles (either triceps or pecs, in this case) during training led to higher activation of the muscle by 20 to 60 percent.

Visualizing the muscle you're training allows the brain to connect to as many muscle fibers as possible during a single contraction and repetition, Forzaglia says. Visualization of the muscle working can enhance contraction of the muscle and vice versa.

"The more fibers we can activate during a repetition, the more we are going to get out of the lift, so therefore, we will be able to move more weight or increase our reps and build strength," he says. "One reason why I think this is very helpful is because it blocks everything out besides the muscle you are training so you will be able to take your training much further adding more intensity."

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While this seems simple (visualize your muscle and squeeze it), it can be challenging to mentally activate or connect with certain muscle groups. For instance, your biceps may be a little simpler to activate and squeeze, as you use them pretty frequently every day. But your lats or rear delts, on the other hand, may be more challenging to contract.

Luckily there are things you can do to facilitate this process. For starters, touching the muscle you're working can help increase recruitment and contraction, Forzaglia says. If you're doing single-arm exercises, you can place a hand on the muscle you're trying to work.

Or recruit your gym buddy. "If you have a training partner, have them, for example, touch your upper chest while doing an incline bench," he says. "Squeeze at the top of the rep and have the tap the muscle in the upper chest. This will give you a greater focus because now you're not only contracting the muscle but a new stimulus is applied to the muscle, helping you focus on it more."

Another way to help improve your mind-muscle connection is to pause at the top of each rep for a moment or two to focus on squeezing the muscle, Forzaglia says. For instance, if you're performing a biceps curl, pause when the dumbbell reaches the top of the motion and squeeze your biceps for two counts before releasing.

Eccentric, tempo-based and isometric exercises are another great way to build up your mind-muscle connection, says Sam Becourtney, physical therapist at Bespoke Treatments in New York City. Try adding a few of these tweaks to your usual exercises to help improve your mind-muscle connection:

• Eccentric: Focus on the lowering or lengthening portion of this exercise, rather than the concentric, shortening portion.
• Tempo-Based: Create and stick to a consistent tempo count for each move (ex. 2 counts to lift, 1 count to hold, 3 counts to lower).
• Isometric: Hold a squeeze at the top of the exercise (concentric portion).

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