TRT: who it is for, what the TRAVERSE trial settled, and what it does and does not improve

Before you read onResearch and educational information for adults, not medical advice. This entry explains one longevity term — what it means, why it matters and what the evidence says — and nothing here diagnoses, treats, cures or prevents any condition. Baseline labs come before anything, and your own physician has the final word. Longevity Bros offers coaching and written research protocols only — we do not sell, supply, source or ship any compound.

What it means

TRT is medically prescribed testosterone — gel, injection or pellet — for men with hypogonadism: symptoms (low libido, fatigue, loss of muscle, low mood) plus a morning total testosterone confirmed low on two occasions, usually under about 10–12 nmol/L (300 ng/dL) depending on the guideline. Free testosterone and SHBG refine the picture; estradiol and haematocrit are monitored on treatment.

It is replacement, not enhancement: the aim is the mid-normal range, and the trials that inform it used that target.

Why it matters for longevity

Testosterone falls about 1% a year after 30, and the fall tracks with sarcopenia, visceral fat, insulin resistance and bone loss. Where the deficiency is real, replacement improves several of those; where it is not, it adds risk without benefit. The lab-confirmed diagnosis is the whole game.

What the evidence says

TRAVERSE (Lincoff 2023, NEJM, 5,200 men aged 45–80 with hypogonadism and cardiovascular risk, 33 months): testosterone gel did not increase major cardiovascular events versus placebo, resolving the question raised by earlier observational data. It did show more atrial fibrillation, pulmonary embolism and acute kidney injury, and no benefit for fracture (fractures were slightly more common) or for depressive symptoms.

The Testosterone Trials (Snyder 2016, 790 men over 65): modest improvements in sexual function, walking distance and mood, a rise in haemoglobin, and increased coronary plaque volume on CT in a sub-study. Lean mass rises by 1–2 kg and fat falls by a similar amount in most trials; strength gains are small without training.

How to measure or use it

Diagnosis: two morning total testosterone readings, SHBG, free testosterone calculated, LH/FSH, prolactin, haematocrit, PSA — then a physician decision.
On treatment: total and free testosterone at 6–12 weeks, estradiol, haematocrit (above 54% is a stop signal), PSA, lipids and ApoB.
Before replacement: sleep, body fat and training raise testosterone by 10–30% in deficient men and are the first step in any protocol.

Hormones after 40 — the full article
Baseline labs — the hormone panel
The lean-mass protocol — where hormones fit next to training

Frequently asked questions

Does TRT cause heart attacks?

TRAVERSE, the largest trial, found no increase in heart attacks or strokes. It did find more atrial fibrillation and clots, which are monitored for.

What testosterone level counts as low?

Guidelines use about 10–12 nmol/L (300 ng/dL) on two morning samples, with symptoms. SHBG and free testosterone refine marginal cases.

Will TRT build muscle?

It adds 1–2 kg of lean mass in trials; strength gains are small without resistance training. It is replacement, not an anabolic programme.

Your own protocol

Want this applied to your own numbers?

Fifteen minutes of intake, your labs, a human-reviewed protocol within about 24 hours, three documents, a free coach call and check-ins through the cycle. €399, follow-up included.

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