What muscle does when you are not using it
Roughly 80 percent of insulin-stimulated glucose uptake happens in skeletal muscle. Less muscle means less storage capacity, which means more glucose circulating and more insulin required to manage it.
Muscle is also an endocrine organ. Contracting muscle releases myokines that influence fat metabolism, brain-derived neurotrophic factor, and inflammatory signaling. This is part of why exercise affects mood and cognition, not just body composition.
Sarcopenia starts earlier than people expect
The decline begins in the thirties and steepens across the menopause transition, when the loss of estrogen removes some of its protective effect on muscle and the anabolic response to protein dulls.
The functional consequence is not visible in a mirror. It shows up as the day getting the shopping up the stairs feels different, or standing from a low chair requiring hands.
The training that reverses it
Progressive resistance training, two to three times a week. Progressive is the operative word: the load has to increase over time or the stimulus disappears.
Cover five patterns, squat, hinge, push, pull, carry. Sets of six to twelve repetitions, ending with two or three left in reserve.
Add power work as you gain confidence: moving a moderate load quickly. Power declines faster than strength and matters most for catching yourself when you stumble.
Walking is excellent and is not a substitute. Cardio protects the heart; load protects the muscle and bone.
Feeding the work
Roughly 1.2 to 1.6 grams of protein per kilogram, distributed across meals, plus enough total energy. Chronic under-eating while training hard produces fatigue and injury rather than muscle.
Creatine monohydrate at three to five grams a day has the strongest safety and efficacy record of any training supplement, including in postmenopausal women, where it also shows promise for bone and cognition.
