Lou Schuler, CSCS

For the first few seconds, as Galpin plunges the surgical equivalent of a post-hole digger into my thigh, it feels like a grade-school bully pressing his knuckle into my leg. Then the sensation shifts into reverse as he pulls out. A grad student bandages the quarter-inch hole while Galpin transfers the excised piece of my vastus lateralis muscle from the needle to a petri dish. I see the sample up close a few minutes later: four parallel strips of tissue, each perhaps a centimeter long and a millimeter wide. Under a microscope they look like four tuna steaks. Galpin estimates that each microfillet contains at least 500 individual fibers. But they wont look appetizing for long. After stewing for a week in a special juice called skinning solution, the color will disappear, and Galpin will be able to pull single fibers from the translucent mass.

Thats when Ill learn what Im made of... or at least what my quads are made of. And that matters for two reasons: first, because the quadriceps muscles are among the bodys biggest, involved in everything from running and jumping to getting up from a chair; second, because leg extension strength, a function of the quads, is frequently tested and may predict your risk of early death from any cause. The combination of fibers in those crucial muscles says a lot about how fit you are now and what youll have to worry about down the road.

<h1> What You Need to Know About Muscle Fibers </h1>

Until recently, scientists thought there were three types of muscle fibers: type I (slow twitch), type IIa (fast twitch), and type IIx (super fast twitch). They also thought the distribution was fixed. So a marathon champion with 90 percent slow-twitch fibers in his thighs was born with this inherent advantage, same as a world-class printer with a predominance of fast-twitch ones.

With new innovations-faster separation techniques and more powerful microscopes-weve learned that muscle fibers are actually a continuum of six types, ranging from slow to fast. Even the word type is outdated. The new nomenclature is myosin heavy chain, or MHC. (Myosin is the component of muscle fibers that initiates a contraction.) Slower-twitch fibers contain more mitochondria, the cell parts that generate energy; theyre also capable of using more fat for energy. Faster-twitch fibers burn glycogen; they can fatigue within minutes of exertion.

Andy Galpin tests the leg strengthof UFC star Patrick Cummins. Leg extension tests may indicate mortality risk.

An untrained, genetically average guy might have some 40 percent MHC I, 30 percent MHC IIa, and 30 percent hybrid fibers, which are either a combination of slow and fast (I/IIa), fast and superfast (IIa/IIx), or all three (I/IIa/IIx). Those hybrids, Galpin says, are sitting in the middle saying, Youre not really doing anything, so Im just going to float to this nebulous spot until you give me something I need to be.

When you commit to a lifting program, many of those hybrids will transition to fast-twitch. It starts within weeks, and in the first year of training, as many as 20percent could change into fast-twitch fibers, increasing your strength and power. With endurance training, the hybrids go the other direction, toward MHC I. Theres no right or wrong or even ideal mix of fiber types; your muscle cells adapt to what you need them to do. Conversely, if you work out for a while and then stop, your well-trained slow- and fast-twitch fibers quickly revert to hybrids, in effect going to the sidelines to wait for their next assignment. Research on astronauts reveals that these kinds of changes can happen in just 11 days in space.

Galpins research has distinguished lineage. It began at the Karolinska Institute in Sweden (the place that chooses the Nobel Prize winner in physiology), wherein 1959 the percutaneous muscle biopsy was modernized. A professor at Ball State University traveled there to learn the technique, and he in turn taught it to Galpin and Jimmy Bagley, Ph.D., a colleague of Galpins, when they were earning their doctorates. Now Galpin and Bagley are taking the research a step further by looking at the structure and function of muscle fibers in people ranging from elite strength and power athletes to end-stage kidney failure patients.

Between those extremes are Paul and PeteMcLeland, 54-year-old identical twins with completely different fitness habits. They gave Galpin and Bagley a remarkable case study showing how fiber types can change over a lifetime. Paul, a high school teacher and track and cross-country coach near Chicago, has been a dedicated runner most of his life. In college he was all-conference in cross-country, and at times as an adult hes gone years without missing a single day of training. Im a plugger, grinding for each mile and minute, he says.

A segment of a single muscle fiber after its been extracted and separated at Galpins lab.

Pete, who notes that hes three minutes older than his brother, always preferred cycling and has biked across the country multiple times. But due to long hours at his sales job and a debilitating ankle injury 12 years ago, he no longer has a regular fitness routine. Their health and fitness profiles are predictable: Paul weighs less and has a lower resting heart rate. His blood work shows lower cholesterol, triglycerides, and blood sugar. But Pete has just as much muscle mass as his brother and smoked him on tests of leg and grip strength. Their muscle fiber biopsies reveal very different adaptations due to their fitness regimens. Pauls muscles adapted to match his singular pursuit, while Petes inactivity resulted in still having 25 percent of hybrids unassigned. The takeaway, Galpin says, is the amazing plasticity of human muscle: With enough time and enough exposure, you have no boundaries.

While Galpins research indicates that major shifts in fiber type (around 25 percent) are possible, its the minor shifts (around 10 percent, from fast to slow or vice versa) that are more common, says Kevin Murach, Ph.D., an exercise scientist at the University of Kentucky. We have a pretty good handle on what type of stimulus elicits a certain kind of switch, but the precise molecular details are elusive. Its likely not just one thing but a combination of things that causes fiber-type transitioning. Another open question is the degree to which genetic pre-disposition plays a role.

Eventually, Galpin says, coaches may be able to design programs based on an athletes specific fiber type mix, or even create programs to change the mix to one more favorable for his sport. Hes already experimenting with a slimmer needle and works with pro athletes doing muscle fiber screening to see if theyre training at peak efficiency. Instead of just guessing at programming, we can say, Yep, this is your issue. Your slow-twitch fibers are garbage.

Those applications still arent available to the public, but in the meantime there are ways you can gauge the effectiveness of your workouts. If youre a rookie or coming back after a layoff, ask yourself: Are you gaining strength and/or speed? Are you increasing your volume-more sets and reps, more intervals, longer sessions? If youre more experienced: Are you maintaining or hitting new maxes for a variety of different lifts and/or maintaining speed at peak levels? Are you maintaining your overall volume of exercise?

\"I love these studies because the endpoint is death-the ones who are stronger tend to live longer.\"

Galpin himself is a bit of a hybrid. At 34, with a compact, wide-shouldered frame, he still looks like the jock he started out as-a small-town kid from Rochester, Washington, who played football at Linfield College, a Division III powerhouse in McMinnville, Oregon, where he won a national championship in 2004. But he paid a big price for glory: Five surgeries on his right knee left him with limited ability to jump, sprint, squat, or do Olympic lifts with a full range of motion.My overall fitness is better for it, he says. Its day-by-day to see what works and what doesnt work, which forces me to be creative.

His creativity leads him in many directions. In addition to his research, he practices Brazilian jiu-jitsu and trains high-level athletes in combat sports (wrestling, boxing, MMA), football, and baseball. He hosts the <a href="http://www.andygalpin.com/" id="1bdcfc4a-cab0-3f3f-aae4-4098e017c169"> Body of Knowledge podcast series </a> , combining stories about the history of exercise science with insights into the latest research. Hes also coauthored a book titled Unplugged, which advocates using less technology in your life and workouts and trusting your body more.

The book only sounds like it contradicts his research. In truth, the more time Galpin spends looking at muscles under a microscope, the more he appreciates how crucial they are to all the things we enjoy in life and to how many years we get to use them. To Galpin, health and fitness are simple, straightforward pursuits. If you look at what predicts mortality-and I love these studies because the endpoint is death-the ones who are stronger tend to live longer.

Cummins does a grip test, a likely indicator of mortality.

But strength isnt the only fitness parameter linked to longevity. Cardiorespiratory fitness is also associated with longer life. So is more total physical activity. The research is unambiguous enough, but the message can get garbled by experts who, despite their generally good intentions, are stuck in fitness silos. Theyre so invested in strength or endurance training that theyre blinded to the value of everything else.

Most doctors and fitness experts will tell you to start with sustained effort-walking, especially. Thats led to the goal of 10,000 steps a day. Thats good, but you shouldnt stop there. Strength is a major part of health, Galpin says. The more strength you gain, the more youll move around during the day. Stronger muscles allow your heart to do its job with less effort, making it easier to do everything from walking and climbing stairs to lift-ing and carrying bags of groceries or sacks of dog food. I mean, what dissuades you from doing those random acts of physical activity? Its not all cardiovascular function. Its also being weak!

Galpins prescription: Do a few things involving heavy weight. Do a few things that get your heart rate up. Do a few things that require sustained effort. Its not sexy, but all the research shows that those three things are the most important, he says. If you workout just three times a week, Galpin recommends this program:

<ul><li> Day 1: Go heavy. Do at least one exercise in each of the five major movement patterns: squat, deadlift, push (chest or shoulder press, pushup, dip), pull (chinup, pulldown, lat pull-down, row), and carry (pick up something heavy with one or both hands and walk). On at least one or two exercises in each workout, go as heavy as you can while maintaining good technique. On a scale of one to 10, it should rate about seven to nine, he says. If you dont push it, you wont get stronger. </li><li> Day 2: Go long. It doesnt matter what you do, as long as you keep up a continuous, sustained effort for at least 30 minutes. You can run, ride, or do calisthenics. Your intensity should be high enough to feel like exercise, but not so high that you have to stop and rest. </li><li> Day 3: Go hard. This time your goal is to get your heart rate up near its max through brief bursts of all-out effort. Again, the specific mode of exercise doesnt matter-you can use a rower or stationary bike, swing a kettlebell, run up a hill. A good target is three to six 30-second intervals, with two to three minutes in between for recovery. </li><li> Beyond Day 3: Go (sort of) heavy again. </li></ul>

If you want to do a fourth session, your best bet is another weight workout, but using moderate weight with the goal of building muscle.

Two days after my biopsy, we sit in a basement room at San Francisco State University, where Bagley operates a laser confocal microscope, a half-million-dollar piece of amazeballs technology. It lets exercise scientists look at individual muscle cells with a degree of three-dimensional precision unheard of until recently. Today were comparing two cells: The first is from a young, athletic woman. The second is from an elderly kidney failure patient whos participating in a study Galpin and Bagley are working on.

Biochemist Irene Tobias, Ph.D., separates muscle fiber segments.

The difference is striking. While the nuclei of the healthy person are neatly positioned and uniformly shaped, those of the unhealthy one look like the floor of a college dorm room, littered with random piles of dirty clothes. It matters because the nuclei hold your DNA. That means they control the growth and repair processes. If they cant repair a fiber, it dies. And dead fibers dont come back, Galpin says.

We dont know which came first, the failing organs or the dying muscle cells. But we do know that in almost every case, daily choices can add up to profoundly different outcomes.Your lifestyle has more of an influence on how your muscle acts and behaves than weve ever really thought, Galpin says. Even if youre born with shitty genetics, you can train your way out of a lot of that. Thats true for all of us, at every age.

Thats on my mind when I receive the results of my fiber analysis 10 days after I return from California. Its worse than I feared. I have 38 percent hybrid fibers-those guys sitting on the sidelines waiting to turn into something specific-and just 12 percent MHC IIa, the ones responsible for strength and power. Considering your age [Im 60], its not that terrible, Galpin says. But, just in case I dont get the point, he adds, Its not amazing either.

There was no risk of me not understanding, not after immersing myself in Galpins world and seeing what happens when good cells go bad. Despite chronically sore knees, I need to get those fast-twitch bastards off the bench and back into the ballgame.

Thats why the next day I found myself using the leg extension machine for the first time in probably 20 years. To my surprise, by shortening the range of motion at the bottom, I could work my quads to a deep level of fatigue with no discomfort at all. The same proved true with the leg press, another machine Ive rarely used in recent years. Over time, if I keep pushing myself, I should get some of my IIa back.

The second part of my comeback strategy is conditioning. Ive been doing intervals, carries, and sled work, but its clear that I need to do a lot more. My biopsy showed 50 percent MHC I fibers, which is probably my low-training setting. Getting a few of my slow-fast hybrids to join the slow side will give the muscles better endurance, and allow them to use more fat for energy.

In the past I could come up with any number of reasons to avoid or truncate the areas of fitness training I didnt enjoy. But now that Ive seen whats inside my muscles, I realize I have no good excuses.

On a Saturday morning in a research lab at Cal State Fullerton, Andy Galpin, Ph.D., C.S.C.S.*D., approaches my left quadriceps with a hollow-point needle designed to extract a chunk of muscle tissue. The sensation, he tells me, will feel like a biopsy. Since Ive never had a biopsy, telling me the procedure feels like itself is like saying moose tastes like moose; the information is illuminating only if youre really into ungulate meat. But Galpin, who estimates that hes bee...

How Scientists Are Learning How to Use Your Muscles to Predict Your Mortality

Why the switch? More than anything, it comes down to Hadza piss.

The Hadza are hunter-gatherers in East Africa who get more exercise in a day than many of us get in a week. When scientists set out to measure the caloric cost of all that hunting and gathering (plus everything else requiring energy), they had them drink water laced with two rare isotopes. After checking the peed-out isotopes and comparing the ratio of one to the other, they could tell how much CO2 the Hadzas produced during that time and, by extension, how many overall calories they burned.

I came into this research assuming that the more activity you get, the more calories you burn, says Herman Pontzer, Ph.D., an anthropologist at Hunter College and one of the architects of this paradigm-changing research. Hed also assumed the converse-that the more time you spend sitting, the fewer calories you burn. So when he conducted a pissing match between the lean-and-hungry Hadza and sedentary office workers, the results shocked him. After accounting for body size, the office slugs had the same energy expenditure as guys who chase giraffes for a living.

Pontzer says its the same across species. The daily calorie burn of a caged zoo animal is the same as that of its born-free counterpart in the Serengeti. Apparently the more active you are, the more your metabolism adjusts to balance the caloric ledger.

What all this means is that no matter how many calories a normal guy burns with exercise, his body will find ways to restrict the number he burns the rest of the day. When researchers compared sedentary people to moderately active people, the active group burned only about 200 more calories a day overall, even at higher activity levels. Thats a far cry from the numbers you see on your fitness tracker. Pontzer calls this constrained energy expenditure. And your metabolism has lots of room for adjustment, given that 50 to 70 percent of energy expenditure goes toward the basic functions of staying alive, 10 percent goes to digesting food, and the rest (20 to 40 percent) is for physical activity.

Depressing? Yes, especially for the millions of Americans who probably wouldnt work out at all if they didnt think it would help them lose weight. But is it really the final word? Not necessarily.

Young shirtless muscular man warming up before a workout outdoors.

Mick DiMaria is a small-framed, 5'7" creative director and writer in Southern California. He kept his weight steady for most of his adult life without much effort, gaining about 10 pounds during the holidays and losing it after the start of the new year. But in my 40s, it wasnt so easy to lose it, he says. At 174 pounds, he was way below the 196-pound national average for men. Still, he says, I was pushing maximum density. So he hired a trainer. Although his initial focus was on building muscle, he started losing weight, averaging a half pound a week. After a little over a year, he was down to 147.

To look at DiMaria today, youd never guess hes 24 pounds lighter. And if you did, you would assume it was because he drastically changed his diet. But he says those changes were modest, like eating more whole foods and making his lunches instead of getting takeout. I never skipped meals, he says. I never gave up anything. I just had less of it.

\"I strongly believe that exercise can contribute to weight loss.\"

DiMaria is hardly the only one. Every trainer has at least one client like him, someone whose body never got the memo about exercise being ineffective for weight loss. Youve probably seen it yourself-the cousin who started working out in his basement and lost his gut, the neighbor who shed 10 or 20 pounds by walking around the block.

Exercise just by itself isnt going to work for the majority of the population. But there are smaller subsets where we see it, says Brian St. Pierre, M.S., R.D., director of performance nutrition at Precision Nutrition. How rare are these subsets? What do these people have that makes them exceptions to the new research? And for your purposes, can you turn yourself into an exception, or must you be born that way? At least one researcher says we may have more control than we think.

I strongly believe that exercise can contribute to weight loss, says Clemens Drenowatz, Ph.D., a professor of physical education at the University of Education, Upper Austria. One reason is a concept called energy flux, or the speed of energy turnover in the body.

Portrait of three macho male cross trainers in gym

Imagine three guys with stable body weights. Two of them have the same daily energy expenditure-say, 3,000 calories. They are both high flux, meaning they take in a lot of calories and burn a lot of calories. But their bodies burn energy very differently. The first guy moves more, both intentionally (by exercising) and unintentionally (by fidgeting and spending more time on his feet). The second guy is pretty sedentary; he has an office job and doesnt exercise much. However, the second guys heavier body requires more energy for movement and just staying alive. So at the end of the day, assuming their calorie intakes remain the same, neither of the two puts on or loses significant weight.

Now consider the third guy. Hes low flux, meaning he takes in and burns fewer daily calories than the other two, but hes also established an equilibrium and his weight remains stable.

Early research from way back in the 1950s suggested that people who move the least may consume more calories than they expend. The more exercise a person gets, the easier it could be to avoid weight gain.

Understanding the concept of energy flux may be the key to understanding the secret of weight loss.

But something else happens at the extremes, something scientists still dont fully understand. Paradoxically, the higher the numbers (calories in/calories out), the leaner you may be and the easier it may be to control fat.

Its borne out by a three-year American Journal of Clinical Nutrition study of teenagers, published in 2016. The scientists found that teens who ate a lot of calories and burned a lot of calories reduced their body fat percentage over those three years, while those who ate little and burned little gained fat. This is despite the fact that teens in the high-flux group were eating several hundred more calories a day than they needed to maintain their weight at the start of the study, while the low-flux teens were eating below maintenance. The combination of high intake and high expenditure was somehow more powerful than either variable in isolation, making them leaner than they shouldve been.

Two handsome shirtless men giving fist bump after successful workout at rooftop gym.

As Drenowatz proposed in a 2017 research review, the quantity of calories people consume is independent of the amount of exercise they get. An active person who becomes sedentary may eat the same amount as before (if not more than necessary) and gain a lot of weight. The extra body mass then raises his metabolism, since it takes more energy to maintain a bigger body. That, in turn, leaves him with the same energy flux he had when he was smaller and more active.

Why would your body do this? Drenowatz thinks the human body seeks a preferred energy flux rather than a preferred bodyweight. Indeed, studies of identical twins have shown that they typically have the same flux, even when their body weights and activity levels differ. The higher body mass of the less active twin allows him to burn the same number of calories as his lighter sibling.

Pontzer says its possible that high or low daily energy expenditure is set early in life, although we dont know what the precise mechanism is. Hes noted two groups that appear to have high expenditure: athletes and subsistence farmers. What do they have in common? They both tend to grow up moving a lot and eating a lot.

Whether its genes, environment, or some combination, high expenditure in childhood may remain intact throughout life, but Pontzer says we dont know for sure. Being predisposed to high energy flux may help some people respond quickly to workouts and have more success keeping their weight stable through exercise, while for some others no amount of exercise affects weight loss. Turns out, this can be the key to healthy weight.

To gauge if exercise could help you easily lose weight and keep it off, ask yourself if you fit into one or more of the following categories:

<ul><li> You were extremely active as a kid but are mostly sedentary now. </li><li> Until recently, you could eat what you wanted without gaining much weight, if any. </li><li> Like Mick DiMaria, youve spent most of your life in pretty good shape and only recently let yourself go. </li></ul>

If any of these ring true, theres a good chance youre high flux. That suggests your body prefers to eat a lot of food each day, and until recently you matched your appetite with a high activity level. And it suggests your body may respond quickly to structured workouts.

The best exercise (no surprise) is whatever you like most and will do consistently. No preference? Drenowatz likes strength training. It increases energy flux four ways:

<ol><li> As Drenowatz showed in a 2015 study, lifters develop more functional strength, which leads to more overall activity between workouts. Endurance training had the opposite effect, leading to less movement between workouts. </li><li> Increased muscle mass overtime raises your resting metabolic rate. </li><li> Hard workouts elevate your heart rate for several hours afterward, burning more calories as your body recovers. But unlike with hard aerobic workouts, there may be less post-exercise fatigue with strength training. So instead of chilling out on the couch, you can continue being physically active. </li><li> Such workouts also increase protein turnover in your muscles. Higher rates of break-down and buildup add to the caloric burn. </li></ol>

In total, Drenowatz recommends more than 300 minutes a week of exercise at a moderate to hard pace, which seems like a less popular guideline than, say, walk 10,000 steps a day. But its not hugely different from the program DiMaria used:

<ul><li> Three full-body strength workouts a week, using relatively heavy weights with the goalof increasing muscle strength and size. ( <a href="https://www.menshealth.com/fitness/a27559454/beach-body-plan-men/">Check out this program</a> for a taste.) </li><li> Two or three sessions a week of running, walking, cycling, or some other endurance activity. Dont go so hard that you compromise your results in the weight room. Pounding your body may trigger the effect seen in the aforementioned study: Youll end up moving less between workouts and neutralize the benefits as a result. </li><li> Diet is tricky, since deliberately eating more is a terrible strategy when youre trying to lose weight. Try what DiMaria did: Eat when youre hungry. But make sure each meal includes at least 20 to 30 grams of protein, which builds muscle, takes more energy to digest, and is satiating. </li></ul>

What if you do everything right and still dont see a significant difference on the scale? The data is really clear that exercise is super important for health, says Pontzer. The health issues that people deal with as they age [heart disease, type 2 diabetes, cancers], exercise helps with all of them.

Drenowatz agrees, adding that the psychological benefits also matter. You feel better when youre more active, and that in turn helps motivate you to make better food and lifestyle choices. Bonus: If youve already lost weight, exercise can help you keep it off.

So even if this basic workout template doesnt help you lose a significant amount of weight, you dont have anything to lose. The worst that can happen is youll get stronger, leaner, and healthier, which isnt such a bad thing to settle for.

For decades, the experts line on exercise and weight loss was simple: Do this much, lose that much. But recently theyve changed their tune: While exercise is awesome for overall physical and mental health, they say, dont expect it to necessarily yield the number one result most guys want when they join a gym.

Everything You Thought You Knew About Burning Fat Is Wrong

Politics

Local

World

News

Celebrities

Music

Movies

Entertainment

Sports 

Fashion

Beauty & Health

Relationships & Weddings

Food & Travel

Lifestyle

Domestic

International 

Business

Explore categories

Checkout our authors for the latest content across entertainment, sports, business and more. Be first to receive exclusive updates with your free subscription straight to your phone | Pulselive Kenya

Authors | Pulselive Kenya

| Pulselive Kenya

Read the latest news across entertainment, sports, business and more. Be first to receive exclusive updates with your free subscription straight to your phone | Pulselive Kenya

Breaking News & Top Stories | Pulselive Kenya

Pulse Kenya is the most followed news and entertainment platform in Kenya. It informs and engages young Kenyans around the clock and provides updates by the hour.

Pulselive Kenya

Search for the latest content across entertainment, sports, business and more. Be first to receive exclusive updates with your free subscription straight to your phone | Pulselive Kenya

Search Results | Pulselive Kenya

Watch the latest videos across entertainment, sports, business and more. Be first to receive exclusive updates with your free subscription straight to your phone| Pulselive Kenya

Lou Schuler, CSCS

Articles written by the author

How Scientists Are Learning How to Use Your Muscles to Predict Your Mortality

Everything You Thought You Knew About Burning Fat Is Wrong