Muscle preservation — peptide, drug, and lifestyle options compared

The 2020s have made muscle preservation a mainstream question for the first time. Two demographic shifts forced it: the GLP-1 era is producing 15–20% body-weight reductions in millions of adults, with ~30–40% of that loss as lean mass; and the geriatric sarcopenia literature has moved from "interesting epidemiology" to "this is the difference between independent and assisted living after 70." Both audiences arrive at the same question — "how do I keep the muscle?" — with very different starting points and very different right answers.

This guide compares the realistic interventions. It is structured around a load-bearing observation: the resistance-training and protein-intake interventions are not optional. Every pharmacological row on this list is most defensible as an adjunct to them, not a substitute. A GH-secretagogue stack without resistance training and adequate protein produces a different result than the same stack with both — and the published trial data does not let you separate the two.

The audience this guide is written for splits roughly in three: people losing weight on GLP-1 agonists who want to preserve lean mass during the deficit, adults 50+ noticing strength and functional decline, and bodybuilding-adjacent recomposition users who want to add muscle in maintenance or recovery contexts. The right answer differs across these three — explicitly flagged in the per-option sections.

The comparison

Option	Evidence tier	Effect on muscle preservation / accretion	Time to outcome	Cost / month (US, 2026 est.)	Side effects	Reversibility	Who should consider	Who should skip
Resistance training (progressive overload, 3+ sessions/wk)	Tier 1 (massive literature; foundational)	Largest single-intervention effect. In caloric deficit, shifts lean-mass-loss fraction from ~30–40% (no training) to ~15–25% (trained)	8–16 weeks	$50–150 (gym, equipment)	Soreness, transient strain risk	Effect builds while training; detrains within ~3 weeks of stopping	Everyone in deficit; everyone over 50; everyone in any peptide protocol described below	No one
Protein intake 1.2–1.6 g/kg, 4 doses ≥30g	Tier 1 (Phillips, Morton meta-analyses)	Maximizes muscle protein synthesis; ceiling effect ~1.6 g/kg in trained adults; older adults benefit from ~1.6 g/kg	Immediate	$30–100 (food + whey)	None at this range; renal-impaired should consult	None — habit	Everyone	Documented advanced renal impairment (CKD ≥ stage 3) without consult
Creatine monohydrate 5 g/day	Tier 1 (largest meta-analytic supplement literature in sports nutrition)	Modest strength + lean-mass effect; meaningful effect on training tolerance especially in deficit; emerging cognitive signal in older adults	4–8 weeks for full effect	$5–15	Water retention (3–5 lb intracellular; cosmetic only); rare GI at higher doses	Reverses within weeks of stopping	Almost everyone training	Renal impairment with no consult; people who interpret water-weight gain as fat
HMB (β-hydroxy β-methylbutyrate) 3 g/day	Tier 2 (positive in untrained / deconditioned; equivocal in trained adults)	Anti-catabolic in catabolic states; small effect in trained populations	4–12 weeks	$20–40	Minimal	None	Untrained returning from injury; older adults; cancer cachexia and similar catabolic states	Trained adults in maintenance — likely small effect
Testosterone replacement (medical)	Tier 1 for hypogonadal men; Tier 2–3 for "normal-low" range	Substantial — restoration of lean mass, strength, training quality in deficient men	12–26 weeks	$30–200 with insurance; $150–400 cash	Hematocrit elevation, lipids, fertility suppression, prostate / cardiac monitoring	Reversible on stop; baseline gonadal function may not return immediately	Lab-documented hypogonadism (consistent low T + clinical symptoms); discussed with a physician who manages this	"Normal-low" T without clinical symptoms; anyone considering this without proper monitoring; women without hormone-specialist guidance
Tesamorelin (off-label; visceral-fat indication)	Tier 1 for FDA-approved indication; Tier 2–3 for lean-mass effect in non-HIV populations	Modest lean-mass benefit via GH-axis; primary effect is visceral-fat reduction	12–26 weeks	$400–800 compounded	Glucose intolerance ~10%; IGF-1 elevation; arthralgia	Effects regress on stop	People in fat-loss cycles who want a GH-axis adjunct with the strongest evidence base on this list	Diabetic; pituitary tumor; pregnancy; expecting dramatic muscle accretion
Ipamorelin + CJC-1295 (DAC) stack	Tier 1 mechanistic (GH-pulse); Tier 3 for lean-mass outcome in non-deficient populations	Modest — supports recovery, sleep, body-composition slow shift over 12+ weeks. Not a primary anabolic	8–16 weeks	$80–150 research suppliers	Water retention first 2–4 wk; transient lethargy; IGF-1 elevation; injection-site reactions	Effects regress on stop	Recovery / recomposition adjunct in trained adults; sleep-quality + body-composition combined goal	People expecting "GH pulse → big muscle gain" — this is a recovery and recomposition tool, not an anabolic
MK-677 / Ibutamoren (oral)	Tier 1 for GH/IGF-1; Tier 2 for lean-mass via Nass 2008 (older adults, 12 mo)	Modest lean-mass gain (~1.1 kg fat-free mass over placebo at 12 mo in Nass 2008, older adults); appetite stimulation confounds	4–24 weeks	$50–80 research suppliers	Water retention, appetite spikes, fasting glucose drift, reduced insulin sensitivity	Water resolves; metabolic effects may persist	Older adults specifically (where Nass evidence applies); people who want appetite stimulation alongside lean mass	Pre-diabetic; long-cycle without breaks; people who confuse water + appetite-driven weight gain with muscle
Anabolic steroids (testosterone esters at supraphysiological doses, other AAS)	Tier 1 for muscle accretion; Tier 1 for harm profile	Largest pharmacological effect on muscle accretion of anything on this list	4–12 weeks	Variable	Cardiovascular (atherosclerosis, LVH, polycythemia), hepatic, fertility / HPGA suppression often permanent, mood / aggression, gynecomastia, dependence	Many side effects persist beyond use; HPGA suppression can be permanent	(See "Who should skip")	Almost everyone reading this. Use without medical supervision carries cardiovascular, hepatic, and fertility risks well beyond the muscle-preservation question this guide addresses. Site policy: no protocols, no dose recommendations, no vendor links. See ipamorelin-vs-steroids critic response for the longer treatment.
Choosing a different goal / acceptance	Tier 1 in honesty	Variable	Immediate	$0	None	None	People for whom the muscle-preservation goal is body-image driven and a different framing would serve better	Anyone with functional or sarcopenia-related decline — that is a health concern, not a body-image one

The top three rows of this table cover ~80% of the effect for most people. Reading down to the GH-secretagogue rows without committing to the top three is the most common pattern — and the most common mistake.

This guide carries the public comparison. The member continuation walks the GLP-1 muscle-preservation conversation in depth, the sarcopenia case for older adults, the per-option evidence, and the founder's view on what to actually do.