HeraSphere #43: Muscle as Medicine

Hi friends,

Strength training has always been my weakness. Literally and figuratively.

For years I treated cardio as the real workout and weights as the optional bonus I added when I had extra time, which was almost never. I knew I should lift more. I just couldn’t motivate myself to do it, because I also didn’t know what to do with the weights.

This is part two of our series on fat burning and muscle building. Part one covered why fat accumulates differently after 40, how to burns it in 3 steps, and why it comes back when you stop moving. This issue is part two, covering what it takes to build the muscle that makes fat loss sustainable, and why muscle is doing far more than most of us realize.

The TL;DR

• Muscle loss starts in perimenopause and accelerates faster than we realize. By the time you notice it in the mirror, you have likely already lost 3 to 8 percent of muscle mass per decade since your 30s. The flat arms and disappearing strength are not inevitable aging. They are a training deficit we can fix.

• Strength training is a central nervous system event and a physical one. The first adaptations are neural, not muscular. Your brain learns to recruit more motor units before your muscles grow. This is why the first four weeks feel hard even with light weights.

• Heavy is relative, and most women are lifting at a fraction of their actual capacity. Heavy means 70 to 80 percent of the maximum you can lift once with good form, for five reps before failure. Most women in group fitness classes are working at 30 to 40 percent of that.

• Muscle is an endocrine organ. Every hard contraction releases signaling molecules called myokines that travel to the liver and instruct it to stop storing visceral fat. Moderate intensity exercise does not produce this signal.

• Protein and creatine support muscle building. One gram per pound of body weight per day supports muscle repair when estrogen-driven breakdown is accelerating. Three to five grams of creatine monohydrate daily supports both muscle strength and brain health simultaneously.

Muscle Loss in Midlife

• Women lose 3 to 8 percent of muscle mass per decade from their 30s, accelerating sharply as estrogen drops. Estrogen is anabolic: it drives satellite cell development, which is how new muscle cells are created, and governs nerve conduction, which determines how powerful a contraction can be. When estrogen drops, muscle breaks down at its normal rate but rebuilds more slowly. Net muscle loss happens even in women still training at the same volume they always have.

• What you are seeing in the mirror is largely muscle loss, not fat gain. The flat arms, the softer glutes, the reduced grip strength are not aging. They are a specific deficit that strength training directly addresses.

• You can preserve muscle with training. Side by side images of a sedentary 74-year-old and an active 74-year-old show almost completely different muscle architecture. The active 74-year-old's tissue looks nearly identical to a 40-year-old athlete's. An 80-year-old who lifts consistently is functionally as strong as a sedentary 60-year-old.

• Less muscle means a smaller metabolic engine. More muscle means more mitochondria, more calories burned at rest, and maintained leptin sensitivity. The fat loss you worked for is not sustainable without the muscle to keep the engine running at the higher rate.

How Muscle Actually Builds

• Every workout is essentially controlled damage. You go in, you stress the muscle, you create tiny tears. That is the catabolic part. Your body is breaking down. Then you leave the gym, you eat protein, you sleep, and your body repairs those tears and builds the fibers back a little thicker and stronger than before. That is the anabolic part. Your body is building back up.

• Recovery is where you get stronger. The workout is just the signal that tells your body it needs to rebuild. The rest days are when the results happen.

• Strength training is a central nervous system response first. Dr. Stacy Sims says: "When we first start lifting a load, our nerves respond. Our brain is recruiting all these muscle fibers to create a contraction." The first four weeks feel hard because your nervous system is learning new motor recruitment patterns, and because your muscles are weak. Soreness in those weeks means your body is adapting.

• The anabolic response is weakened in perimenopause. When estrogen drops, the catabolic breakdown continues at its normal rate but the anabolic rebuild slows. The fix is not more volume. It is heavier load, adequate protein, and full recovery between sessions.

• Progressive overload keeps the adaptation running. Your body adapts to a given load within four to six weeks and stops signaling for more muscle. Adding weight, reps, or sets regularly keeps the stimulus strong enough to drive continued synthesis. The weight you started with three months ago is now maintenance, and you need to add on to continue the momentum.

• Muscle talks to the rest of your body. Every hard contraction releases myokines, signaling molecules that travel to the liver and tell it to stop storing visceral fat and convert stored fat into free fatty acids the muscle's mitochondria can burn as fuel. Myokines also trigger GLUT4 proteins, which are the doorways in muscle cells that allow glucose to enter from the bloodstream, directly reducing insulin resistance. This is a change at the cellular level in how genes express themselves: the intensity has to be high enough to generate the cascade. Moderate intensity does not stimulate these changes.

• Every hard workout is feeding your brain and your muscles. When you push hard enough to feel that burning, breathless effort, your muscles produce lactate, and your brain actually prefers lactate as a fuel source. Women have fewer of the muscle fiber type that produces lactate than men do, and lose them faster with age. Brain metabolism shifts in perimenopause in a way that tracks directly with Alzheimer's risk, partly because the brain is getting less of the fuel it runs best on. Sprint intervals and heavy lifting produce lactate. A comfortable walk does not. Every hard session is delivering preferred fuel to your brain and building resilience against Alzheimer’s.

What Lifting Heavy Actually Means

• Heavy is defined by your one rep max. Find the heaviest weight you can lift once with good form before failure. That is your one rep max. Heavy training is 70 to 80 percent of that number, for five reps per set. For a bicep curl where your one rep max is 20 pounds, heavy is 15 to 16 pounds for five reps. Most women are working at 30 to 40 percent of their one rep max and wondering why nothing changes.

• Use rating of perceived exertion if you don't want to calculate percentages. On a scale of one to ten, your working sets should feel like an eight. Hard enough that more reps would be a real struggle. That is where adaptation happens.

• Three-minute rest periods between sets are non-negotiable. You are training the nervous system, not burning calories. The nervous system needs full recovery to fire at the same intensity again. Cutting rest periods turns strength training into moderate-intensity cardio, which is exactly the wrong stimulus. Perimenopausal women are already running higher baseline cortisol. Moderate intensity work that never allows full recovery compounds that load without producing the adaptation signal you need.

• Women consistently underestimate their strength. Dr. Vonda Wright sees women gravitating to the ten-pound dumbbells. Her instruction is to put them down, pick up the next weight, do a few reps, then go heavier again. "Women have been so conditioned to do 10 to 15 reps to get toned and not really put in the work they need to build muscle. You're underestimating yourself. Don't cheat yourself with the strength training."

The Exact Protocol

• Three total-body heavy lifting sessions per week. Session one, squat focus: three sets of five reps at 80 percent effort, three minutes recovery between sets, then two sets of three at 85 percent. Session two, hinge focus: deadlifts, hip thrusts, Romanian deadlifts, same loading. Session three, push and pull: bench press, rows, overhead press.

• Sprint intervals after lifting extends the fat oxidation window. The adrenaline from heavy lifting is still elevated when you finish your last set. Adding two to three rounds of 30-second all-out sprints with full recovery at the end of a strength session keeps fat mobilization running while the hormonal environment is already primed. Dr. Wright's sprint protocol: four rounds of 30 seconds at maximum effort, full recovery between rounds. Dr. Sims' recommendation: keep sprint intervals at genuine all-out intensity, not moderate effort, for the hormonal cascade to activate.

• The Norwegian 4x4 for VO2 max, once per week. Four minutes at maximum uncomfortable intensity, four minutes recovery, four rounds. VO2 max is your body's maximum capacity to use oxygen during exercise, and one of the strongest predictors of longevity. This is the evidence-backed protocol for building it from the researchers themselves.

• Zone 2 and daily movement on the other days. Walking, easy movement, your steps. Zone 2 means low enough intensity that you can hold a conversation, roughly 60 to 70 percent of your maximum heart rate. This is good for cardiovascular health and recovery. Moderate-intensity steady-state cardio sits in no-man's land: too hard for recovery, too easy to trigger adaptation.

• If you are starting from zero. Ten minutes of bodyweight movement three times a week. Squats, pushups, hip hinges, light overhead press. Start the sprint component as a 30-second brisk walk at your fastest pace and build from there.

• A free resource I’m using for strength training is Caroline Girvan's Iron Series on YouTube. Free, progressive overload-based, easy to follow compound movement structure.

What You Need to Eat to Build Muscle

• Most perimenopausal women are under-eating. Dr. Sims' most common case: a woman in her mid-40s doing everything right, gaining fat, so she cuts calories and increases training. Dr. Sims' response: drop the volume, increase the food. "Women who are stressed out and really super busy don't eat enough."

• The protein target is 1 gram per pound of current body weight per day. Current weight, not goal weight. As weight comes down, intake adjusts with it.

• Get 20 to 30 grams of leucine-rich protein within 45 minutes of a strength session. Leucine-rich means high in the specific amino acid that triggers muscle protein synthesis. The post-workout window matters more for perimenopausal women than for younger women because the reduced hormonal environment slows muscle repair.

• Animal and plant proteins are not interchangeable gram for gram. Animal proteins, meat, fish, eggs, and dairy, contain all nine essential amino acids in the proportions your body needs, with 8 to 12 percent leucine content. Most plant proteins are missing one or more essential amino acids and average 5 to 6 percent leucine. Plant-based women can build muscle effectively, but need 15 to 20 percent more total protein to compensate, and should combine sources to cover the full amino acid profile. Pea protein is the strongest single plant source.

• Carbohydrates support muscle building, not just fat storage. Fruit, vegetables, and whole grains feed the gut microbiome and provide glycogen, the stored form of carbohydrate your muscles use as fuel during hard training sessions. Cutting carbs aggressively while training hard is under-fueling, and under-fueling triggers the famine response that stores fat and breaks down muscle. Time complex carbohydrates around sessions.

• Creatine monohydrate is the most evidence-backed supplement for women in midlife and most women have never taken it. Three to five grams per day increases phosphocreatine, the immediate fuel source your muscles use for explosive high-intensity effort, in muscle cells. There is no loading phase required.

  I use Nutricost Creatine Monohydrate.

• What 100 grams looks like on a normal day:

  • Breakfast: 2 eggs plus 1 cup Greek yogurt with berries: 28 grams

  • Lunch: large salad with 4 oz chicken, chickpeas, feta, pumpkin seeds: 40 grams

  • Dinner: 4 oz salmon with roasted vegetables and edamame: 35 grams

  • Total: 103 grams. No powder required.

• Add Dr. Sims' protein coffee: protein powder stirred into milk of choice plus espresso, refrigerated overnight. Thirty grams of protein in your morning coffee.

• Protein by food source:

Intermittent Fasting Works Differently in Female Bodies

• The male and female stress responses to low calorie intake are biologically different. The male hypothalamus is less sensitive to nutrient deficits. Men lean up and become more cognitively focused in low-calorie states. The female hypothalamus reads low calorie intake as famine: store fat, suppress reproduction, reduce metabolic rate. The fasting research showing positive results in men is working with male biology.

• Extended fasting in perimenopausal women triggers the fat storage response. Cortisol rises, the brain's hormonal command center begins suppressing estrogen and progesterone production, and the body shifts into visceral fat storage mode. Perimenopausal women are already running higher baseline cortisol. Adding an extended fast compounds that load and often produces the opposite of the intended effect.

• A 12 to 14 hour overnight fast is the practical sweet spot. Finish dinner by 7pm, eat breakfast between 7 and 9am. Beyond 14 to 16 hours, the cortisol cost starts to outweigh the insulin benefit for most perimenopausal women. I’ve switched my intermittent fasting to 14/10, and noticed that my cycle is more regular as a result.

Why the Scale Will Mislead You

• Fat loss and muscle gain can occur simultaneously while the scale barely moves. Losing two pounds of fat while gaining two pounds of muscle is a meaningful body composition change. The scale reads it as nothing happened. This is the most common reason women abandon strength training just as it starts working.

• Body recomposition is real, particularly for perimenopausal women. Research confirms it is achievable for women returning to training, women new to resistance training, and women in perimenopause where the hormonal environment is shifting. All three describe most of the women reading this.

• You need a tool that measures both. If you have a gym with an INbody machine, that is great. My at home Hume Body Pod tracks fat mass, muscle mass, visceral fat, and 42 other metrics in under 60 seconds with 98 percent accuracy compared to a DEXA scan, the gold standard clinical test for body composition. It is what my husband and I use. Watching visceral fat go down and muscle mass go up, even when the total weight barely moves, is what keeps motivation alive when progress feels slow.

What I'm Actually Doing

Strength training is now the non-negotiable anchor of my week. Caroline Girvan's Iron Series on YouTube, two to three times a week. Free, progressive overload-based, with compound movement structure.

For sprint intervals, I don’t run, so I do the Norwegian 4x4 once a week on my C2 rowing machine. I wear my weighted vest to walk on the track during my middle daughter’s practices, doing 30 seconds are full speed, then recovering. Racing my youngest daughter up the hill into her preschool building is thirty seconds is another mini sprint!

I get 10K steps daily by walking during my meetings with an under desk walking pad and sit to stand desk converter.

My husband, son and I each use Nutricost Creatine Monohydrate, 5 grams daily in water.

The Hume Body Pod keeps our family focused on the body composition numbers vs. weight itself.

See you in the weight room,

Lilly

P.S. If you have a friend spending hours on the treadmill wondering why nothing is changing: send this her way. The answer is not more cardio, its building muscle.

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Note: While I love diving deep into research and sharing what I've learned about women's health and wellness, I want to be crystal clear: I'm a passionate health advocate and researcher, not a medical professional. Think of me as your well-informed friend who does extensive homework – but not your doctor.

Everything I share in HeraSphere comes from careful research and personal experience, but it's meant to inform and inspire, not to diagnose or treat any medical conditions. Your body is uniquely yours, and what works for one person might not work for another. Always consult your healthcare provider before making significant changes to your diet, exercise routine, or wellness practices, especially if you have underlying health conditions or take medications.

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