Muscle Up

Regardless of age or athletic ability, a healthy muscle mass works to prevent injury and even increase your lifespan. Read on to stretch your knowledge of these elastic tissues and bulk up on the connection between strength and longevity, plus gain tips for the lifelong care of your skeletal muscles

WRITTEN BY Stratton Lawrence
PHOTOGRAPHS BY Scott Henderson

Abs and biceps may hog the spotlight, but our bodies have more than 650 muscles that allow us to walk, sit, chew and yes, flex. Although most of us aren’t ever going to look like bodybuilders, the value of growing our muscles goes beyond feeling attractive.

Healthy muscle mass has a direct correlation to longevity. Even an hour a week of strength-building resistance exercise noticeably reduces your risk of cardiovascular disease and death by any cause. A 2019 study drawing that connection used 12,500 subjects with a median age of 47, meaning that even if you’ve never before lifted a weight in your life, you can still extend your lifespan through muscle building.

“Unfortunately, our daily routines—even if they include carrying grocery bags or loading kids into car seats—probably aren’t enough to make a difference,” says Dr. Heather McIntosh, a Roper St. Francis Healthcare affiliated orthopaedic surgeon. “There’s a misconception that normal daily activities like walking and climbing stairs will maintain strength as we age.”

To slow the natural atrophy of our muscles that starts in our 40s, or to reduce our chance of injury in old age, we need to actively care for our muscles. That starts with understanding how to build and maintain muscle tissue

The Body’s Build

Muscles make up over 50 percent of our body mass. These fibrous, elongated cells move our bodies by contracting based on signals sent from the brain. We have three types of muscle tissue:

• Cardiac muscles in the heart
• Smooth muscles that give shape to hollow organs
• Skeletal muscles attached to our bones

From our pinky toes to our eyelids, skeletal muscles are the ones over which we have voluntary control. Because they’re in constant use, whether it’s standing up from bed in the morning or typing at a desk, our muscle cells are in a constant state of degradation (MPB, or muscle protein breakdown) and repair (MPS, or muscle protein synthesis).

Resistance exercise like weight lifting helps to increase the ratio of MPS over MPB, creating muscle growth. But as we age, the balance shifts in favor of MPB, resulting in atrophy. That loss of muscle mass is why seniors are more prone to falling—and why there’s less muscle cushion to protect their bones from breaking when they do.

Beyond providing strength, bone protection and better balance, our skeletal muscles also support our body’s other systems. Encouraging muscle growth via exercise boosts our metabolism, helping our organs to function at their best and reducing fat accumulation. In turn, healthy muscles are associated with improved immunity. During our fights with long-term diseases such as cancer, where our immune systems become exhausted, our muscles step up as a source of additional T cells, literally keeping us alive.

Healthy & Strong

To grow—or maintain—our muscle mass, we have to take action to encourage MPS. The good news is studies demonstrate that even 90-year-olds can significantly increase their muscle mass within a few months of beginning resistance exercise, giving them greater balance and mobility.

“Strength training is key,” says Dr. McIntosh, whose personal routine includes weight lifting, yoga and HIIT workouts (high-intensity interval training that combines resistance exercise and cardio). “You can maintain your cardiovascular health by walking or doing your daily activities, but you need to do muscle-strengthening exercises to support the rest of your body.”

One misnomer Dr. McIntosh often hears is “lean muscle mass.” All muscle cells are “lean,” so this really refers to the overall ratio of muscle versus fat in a person’s body. When there’s an imbalance caused by excess weight from stored fat, more pressure gets put on our muscles, ligaments and tendons, leading to a higher likelihood of injury. That can have a spiraling effect—if we’re laid up for several months with a torn knee ligament, our muscles begin to atrophy, and we’re at a higher risk of another injury even after recovery.

With this perspective, the importance of maintaining a strong muscular system—and how it can lead to a longer, more active life—becomes especially clear. In a study of adults over age 55, participants with the highest percentage of muscle mass had a significantly lower mortality rate a decade later than those with the least muscle.

In addition to exercise, nutrition plays a role in muscle building. Foods high in protein but low in fat (i.e., chicken, beans, nuts) provide fuel for muscle growth without encouraging fat accumulation. Sufficient hydration (a gallon a day for men, three quarters of a gallon for women) is also critical for transporting the nutrients your muscles need to grow.

Breaking Down Problems

As an orthopaedic surgeon, Dr. McIntosh typically sees patients after they’ve already suffered an injury. “Often, patients don’t understand why their legs are giving out or their knees are buckling, and they think there’s something structural or mechanical going on, when it’s really that their muscles have gotten weaker over time.”

It’s natural for muscle breakdown to outpace muscle synthesis once we reach midlife, but if we don’t take action to counter that, our bodies become a time bomb ticking down to a debilitating accident. The three most common muscle injuries are strains, tears and contusions:

• Strains: These “pulled muscles” occur when we stretch or overuse a muscle, causing microscopic tears in our muscle fibers. After a strain, we feel weak and sore in the area of injury. The best prevention for strains is stretching.
• Tears: More serious than a strain, a tear can also rip apart blood vessels supplying muscle tissue. These are serious injuries that typically require surgery and subsequent physical therapy.
• Contusions: Also called a bruise, the blue color of a contusion occurs when muscle tissue is crushed and damaged blood vessels release blood under the skin.

Children and active young people frequently suffer from muscle injuries, and often recover quickly. But as we age, if we lose muscle mass, we become more susceptible to injuries during normal day-to-day activities. We shouldn’t look to children or elite athletes as examples for typical injury recovery times. An ACL tear in a soccer player who works daily with a trainer to build muscle mass is going to heal much faster than the knee of a weekend warrior relegated to a desk for the majority of the day.

“A professional athlete has options like cryotherapy and ultrasounds and tools to stimulate muscle fibers available to them every day,” says Dr. McIntosh. While we may not have our own dedicated trainer, there are lessons to be learned from those who do. Over time, athletes create muscle memory. It’s not unlike riding a bike for the first time in years—your body just “knows” what to do. Likewise, when a well-conditioned body suffers an injury, the other strong muscles around the injured muscle can support and carry the patient through their recovery. “Elite athletes have created a strong connection between their muscles,” Dr. McIntosh says, contrasting that to patients who haven’t conditioned their muscles and ultimately fail in recovery because they haven’t built muscle memory.

With any serious strain or potential tear, Dr. McIntosh recommends getting a doctor’s opinion. Although our muscle cells are able to heal quickly, a full tear can’t adequately recover without being reconnected. “If a muscle is torn, that bridge from point A to point B is gone,” she explains. “If it’s not repaired, you can’t use that muscle, and it will atrophy to the point of no return.”

In addition to any necessary surgical repairs, Dr. McIntosh emphasizes the importance of physical therapy. “Once your muscles start to atrophy following an injury, it can take more exercise than you were doing before to build them back up.”

Flex Time

Can you stand up from a chair without rocking your body or using your arms? Or sit without plopping down? That’s the top indicator Dr. McIntosh uses to evaluate the strength of her older patients. If a person’s hips and legs can’t support them rising and sitting, their muscle mass is likely not sufficient to prevent them from, say, breaking a shoulder or wrist in a fall. “Even a small amount of physical therapy can get older patients to that level of functionality, which also gives them more independence,” says Dr. McIntosh.

In younger patients, she uses a single-leg squat as a baseline. “If you stand on one leg and squat down, you want to be balanced and not wobbling,” she explains. “That’s the minimum level of strength you need in your hips to prevent injury.”

Dr. McIntosh sees patients who regularly run or bike but don’t engage in any strength-based cross training. “If you’re a runner, or you jump (like a basketball player), you’re going to run faster and jump higher if you strength train than if you only run and jump.”

Similarly, she encourages a daily stretching regimen that focuses on spine, hip and hamstring flexibility. And for patients short on time or equipment, she recommends body-weight strengthening exercises like push-ups, sit-ups and resistance band work.

“Whatever the exercise, you want to be able to do three sets of 10 reps without pain or fatigue before you advance,” says Dr. McIntosh. You should expect to be sore—don’t try to train the same muscles each day. “Rotate through an arm day, a leg day and a stretch day, so that you’re always giving your muscles a rest after you exercise them.”

Most importantly, Dr. McIntosh stresses that everyday normal activity is not going to maintain muscle strength. “But if you work out to build muscle strength, you will prevent injuries, and you’ll recover faster when they do occur,” she says.

In short, putting in the time now could save you months or years of rehabilitation time later—and could quite literally save or extend your life.