Is Endurance Training Killing Your Strength?


The second that lingered in my thoughts after a latest triathlon-science conference got here from a panel dialogue with “gold-medal coaches,” together with Iñaki Arenal, head of the Spanish high-performance group, and Malcolm Brown, coach of the Olympic-medal-winning Brownlee brothers. I requested the coaches to call the only greatest change in elite triathlon coaching in 2017 in contrast with a decade earlier. The solutions had nothing to do with wearable tech or secret exercises. Instead each gave the identical reply: energy coaching.

Of course, endurance coaches have been preaching the advantages of energy since athletes wore togas. But the sensible actuality of mixing endurance and energy coaching has at all times been trickier than the speculation, thanks partly to an obvious “interference effect” between the 2 exercise sorts. To get one of the best of each worlds, it’s a must to take a better have a look at the molecular alerts concerned in energy and endurance coaching—and determine tips on how to maximize each on the similar time.

The classic study on concurrent energy and endurance coaching was printed by Robert Hickson in 1980. After ten weeks of critically intense endurance coaching, energy coaching, or each, the decision was that energy coaching didn’t hinder endurance positive aspects however endurance coaching did hinder energy positive aspects. Here’s what the energy modifications within the 3 teams regarded like (from a graph redrawn by University of California Davis researcher Keith Baar in this paper):

(Courtesy Sports Medicine)

Initially the concurrent group positive aspects energy, however after some time the outcomes begin to tail off and even reverse.

It’s value noting high triathlete like Alistair Brownlee isn’t needed involved with packing on muscle—in actual fact, that may very well be a adverse. Instead, based on Brown, the roughly 3 hours per week Brownlee spends within the fitness center are primarily centered on constructing sturdiness, in order that he can survive the 30-plus hours he spends swimming, biking, and operating. The problem is way extra acute in sports activities like rowing, which contain big endurance-training volumes but in addition require as a lot muscle mass as you possibly can muster. And from a well being perspective, leisure endurance athletes like me usually battle to put on and maintain muscle whereas racking up miles.

Hickson’s outcomes supplied proof that the “skinny endurance athlete” phenomenon isn’t solely as a result of endurance athletes can’t be bothered to do energy coaching, are too drained to do it proper, or are genetically wired to haven’t any muscle. (Though all these components in all probability play some position.) Instead there appears to be some underlying battle between energy and endurance diversifications.

One rationalization of the interference impact goes one thing like this: Resistance coaching prompts a protein referred to as mTOR that (by means of a cascade of molecular alerts) ends in larger muscle tissue. Endurance coaching prompts a protein referred to as AMPK that (although a special signaling cascade) produces endurance diversifications like elevated mitochondrial mass. AMPK can inhibit mTOR, so endurance coaching blocks muscle progress from energy coaching.

This has been the prevailing image for the previous decade or so, based mostly on cell tradition and rodent experiments. In people, although, it doesn’t seem to be that simple. Instead, based on Baar, one of many leaders in making use of molecular biology to check coaching diversifications, the important thing level could also be extra simple. By the midway level of the well-known Hickson examine, he estimates that the strength-training group was burning 2,000 energy per week of their coaching whereas the concurrent coaching group was burning 6,000 energy per week.

There’s now rising proof of an alternate molecular-signaling pathway during which metabolic stress—not simply from endurance coaching but in addition from different triggers like caloric deficit, oxidative stress, and getting old—hinders muscle progress. This alternate pathway entails a fancy collection of hyperlinks between a “tumor suppressor” protein, one other protein referred to as sestrin, and numerous different obscure acronyms. But particulars apart, what’s notably intriguing concerning the speculation is that it’s extremely delicate to the presence of the amino acid leucine, which binds to sestrin and triggers the synthesis of recent muscle protein. And this, Baar says, suggests some methods to beat (or no less than reduce) the interference impact.

The resolution isn’t so simple as simply consuming extra. Even should you efficiently steadiness caloric consumption with expenditure over the course of a day, you should still find yourself doing all of your energy exercises in a low-energy state. So it’s essential to give attention to getting again into “energy balance” earlier than hitting the fitness center. If you’ve been out driving for a couple of hours, it will take greater than an power bar and a scoop of yogurt.

The most attention-grabbing level, for my part, is Baar’s suggestion that you must design your energy exercise to make use of heavy weights so that you simply attain failure after comparatively few reps. This will maximize the metabolic alerts for muscle progress, whereas minimizing the energy burned and metabolic stress. (Lifting to failure additionally ensures that the previous few reps are completed slowly, which can lower tendon stiffness and scale back harm threat, he factors out.) He advocates lifting 1 set for every train, with masses chosen to goal for the next repetition ranges:

  • Upper physique, compound actions: 6–8 reps
  • Upper physique, isolation actions: 6–10 reps
  • Lower physique, isolation actions: 10–12 reps
  • Lower physique, compound actions: 20–25 reps

As you get stronger and hit the higher finish of those ranges earlier than hitting failure, enhance the load for the following exercise.

The position of leucine suggests it’s particularly essential to get sufficient protein all through the day, to guarantee that muscle-growth alerts aren’t suppressed by a leucine scarcity. A pre- or postworkout shake isn’t adequate; as an alternative goal for about 0.25 grams of protein per kilogram of physique weight, 4 to 6 instances a day. For a 150-pound particular person, that’s a small tuna sandwich and a glass of milk. If you’re coaching critically, chances are you’ll want a higher protein hit—0.4 grams per kilogram—to get the identical impact.

Does exercise order matter? In the normal mTOR versus AMPK image, you’re higher off doing endurance earlier than energy coaching. That’s as a result of the endurance alerts solely keep elevated for about an hour following train, whereas energy alerts keep on for 18 to 24 hours. But within the revised image, the place metabolic stress is the important thing, the order of exercises is much less essential than your power steadiness.

Finally, it’s essential to level out that you simply shouldn’t stress about this except you’re coaching fairly rattling laborious. As a basic rule of thumb, should you’re not doing endurance coaching four or more times a week, or pushing your exercises (i.e., sustaining above 80 p.c of VO2max), you’re unlikely to be hurting your energy positive aspects.

Will following the following pointers remodel scrawny endurance athletes into muscled marvels? Not in a single day. But understanding what’s occurring on the mobile stage can assist optimize our coaching decisions, even when the speedy results are invisible. As Baar places it, “What we can’t see sets the parameters for what we can see.”

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(Editor references)

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