Amid growing buzz around lifespan and healthspan, a new \u201cspan\u201d is entering the conversation: musclespan. Coined and championed by Dr. Gabrielle Lyon,<\/a> the term shifts the focus toward how long our muscles remain strong, functional, and metabolically healthy. It\u2019s an increasingly important distinction as more evidence links muscle health to cognitive health, metabolic function, and all-cause mortality.<\/p>\n If you\u2019re an avid Muscle & Fitness<\/em> reader, you care about muscle and already understand its value as a longevity organ. Yet Lyon worries that even now we may be missing the bigger picture.<\/p>\n \u201cWith the rise of widely available weight loss solutions, many people still prioritize focusing on losing fat as opposed to building muscle,\u201d Lyon, a board-certified physician and founder of Muscle-Centric Medicine<\/a>, told M&F<\/em>. She believes we\u2019re standing at familiar crossroads. \u201cThe obesity epidemic really started in the \u201970s,\u201d she explains. \u201cBut at the same time, there was absolutely no mention of muscle health. Skeletal muscle wasn\u2019t even formally recognized as an organ system until the early 2000s.\u201d<\/p>\n Now, she warns, history may be repeating itself. \u201cI have concerns we\u2019re going to repeat what we did in the \u201970s with the use of GLP-1s without training and appropriate protein,\u201d she says. \u201cPatients 100% will lose muscle, and no physician is prepared to deal with it because we\u2019ve never been in this position ever.\u201d<\/p>\n Lyon defines musclespan as the length of time your muscle stays functional, strong, and metabolically healthy. And not just during your peak years, but how well that tissue holds up over decades.<\/p>\n Skeletal muscle plays a central role in long-term health outcomes. According to Lyon, many of the conditions that accelerate aging<\/a> and increase all-cause mortality risk are not primarily diseases of fat, but of compromised muscle.<\/p>\n \u201cWhen we think about longevity, what are the outcomes we want to avoid?\u201d Lyon raises the question. \u201cDementia, cardiovascular disease, obesity, diabetes, all of which are not around the pathology of fat, but focused on the health of skeletal muscle.\u201d<\/p>\n Musclespan positions skeletal muscle as a central organ system that influences metabolic control, vascular health, and brain function simultaneously. In Lyon\u2019s point of view, preserving muscle quality and function over time is foundational to aging well.<\/p>\n \u201cThe question isn\u2019t just how strong you are now,\u201d she says. \u201cIt\u2019s how long your muscle stays healthy enough to protect you.\u201d<\/p>\n One of the least appreciated roles of muscle is its connection to brain health<\/a> and cognitive function.<\/p>\n \u201cWe know that the stronger the leg muscles, the better the cognition,\u201dLyon says, noting that resistance and aerobic training both play a role.<\/p>\n But the relationship goes deeper than improved blood flow. \u201cA large portion of the brain is designed for movement,\u201d Lyon explains. \u201cIf you are not exercising your body, then there are portions of your brain you are not maintaining. There\u2019s this bi-directional relationship.\u201d<\/p>\n Even movement speed matters. \u201cThe faster you move, the faster you think,\u201d she says, describing how the speed at which you move is linked to processing speed and mental tasks.<\/p>\n A major challenge to musclespan is that muscle tissue changes with age.<\/p>\n \u201cIt becomes more difficult as you age not just to put on muscle, but to maintain muscle,\u201d Lyon says. \u201cThe tissue becomes more anabolically resistant, meaning it\u2019s less efficient at utilizing protein.\u201d<\/p>\n Compounding the problem is what she calls a \u201cdietary mismatch\u201d for muscle health.<\/p>\n \u201cThe average American is eating 300 grams of carbohydrates a day<\/a>,\u201d Lyon notes, \u201cwhich is essentially three glucose tolerance tests.\u201d When muscle makes up roughly 40 percent of body weight, chronically overfeeding carbs while underfeeding protein has consequences.<\/p>\n \u201cIf muscle is chronically inflamed or has low-grade inflammation,\u201d she says, \u201cthat\u2019s a problem.\u201d One of the fastest ways to make muscle \u201creally sick,\u201d she adds, is to stop loading it and stop nourishing it appropriately.<\/p>\nWhat Is Musclespan?<\/h2>\n
Musclespan\u2019s Connection to Brain Health<\/h2>\n
Why Aging Makes Muscle Harder to Build and Easier to Lose<\/h2>\n
The Non-Negotiables for Musclespan<\/h3>\n
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