Let's Be Honest — TRT Isn't What Most People Think It Is
TRT isn't a shortcut or a magic fix. It is hormone replacement to restore a functional baseline, prescribed and monitored, and it only works safely with bloodwork before you start and on a fixed schedule after. Get the basics right first, or you're just paying for better numbers on paper. I'm going to be straight with you from the start: I spent a long time reading about testosterone replacement therapy before I did anything about it. And a lot of what I read was either scaremongering on one end or outright fantasy on the other. Neither was particularly useful. What I actually found, through research, bloodwork, and time, was something far more practical and far less dramatic than either camp suggested. TRT isn't a shortcut. It isn't magic. And in Ireland, where quality information on this is genuinely hard to come by, I think that's worth saying clearly.
Why I Started Researching This
I was sitting at around mid-80kg, training consistently, eating well by most people's standards, and still feeling like something was off. Recovery was slower than it should have been. Sleep wasn't restoring me the way it used to. I wasn't in bad shape, but I wasn't making the progress that the effort I was putting in should have produced. I had bloodwork done — not because I was convinced something was wrong, but because I wanted actual data rather than guesswork. That's where the conversation around TRT started for me. The numbers told a story that my day-to-day experience was already hinting at. From that point, I started taking the research seriously.
What the Research Actually Says
Studies indicate that testosterone plays a significant role in muscle protein synthesis, red blood cell production, bone density, libido, and mood regulation. Research suggests that when testosterone levels fall below an individual's functional range — not just a clinical threshold, but the level at which that person actually operates well — a range of symptoms can follow, including fatigue, reduced recovery capacity, and changes in body composition. The mechanisms are reasonably well understood at this point. Testosterone binds to androgen receptors in muscle tissue, influencing the rate at which the body can repair and build muscle. It also interacts with the hypothalamic-pituitary-gonadal axis, which is why exogenous testosterone suppresses natural production and why protocol design and monitoring matter so much. Research also consistently points to the importance of managing estrogen conversion, hematocrit levels, and lipid panels when testosterone is introduced. This isn't an area where you can fly blind and expect things to go well.
My Personal Experience
I use a consistent regimen split across the week, set and adjusted by the doctor who reads my bloods. I am not publishing the amount or the frequency. My own numbers are between me and him, and written on a fitness page they stop being my experience and start being somebody else's plan. Anyone who needs those numbers needs a doctor, not a website.
What I will publish is what I watch, because that part is genuinely useful. HDL first. Then LDL and ApoB, triglycerides, haematocrit, blood pressure, liver, glucose, kidney markers, sleep, and how I actually feel day to day. HDL is the one I care about most, and it is not theoretical for me: it dropped during a heavy phase and came back into the normal range later. Nothing about how I felt told me either of those things was happening. That is the whole argument for testing. The heart side of the list is a topic on its own, and how I approach cardiovascular protection with data covers what I watch and why I would rather see it early than late.
Here's the honest part though, and it took me longer than I'd like to admit to fully understand this: TRT is the foundation everything else sits on. Without dialling in the basics — sleep, training, nutrition — TRT just means healthier stats on paper. I learned that the hard way. There was a period early on where I thought getting the protocol right would carry a lot of the weight. It doesn't. What it did was remove a ceiling that had been limiting what consistent training and decent nutrition could produce. But the work still has to be there. The ceiling lifts. The house still has to be built.
The change I noticed most wasn't dramatic. It was the absence of something — that low-level fatigue that had become normal enough that I'd stopped noticing it until it wasn't there anymore. Recovery between sessions became measurably more consistent. I started sleeping more deeply. These are the kinds of changes that don't make for exciting content online, but they're the ones that actually matter over time.
Adding Retatrutide to the Picture
More recently I've added retatrutide alongside the TRT protocol above, during a deliberate six-week calorie deficit. Retatrutide is a GLP-1/GIP/glucagon triple agonist — the same drug class behind Mounjaro and Wegovy, but hitting a third receptor as well. The established mechanism is appetite regulation and slower gastric emptying, which in practice meant the deficit felt far more manageable than previous cuts I've done on TRT alone — less of the constant hunger that usually wears down adherence by week three or four.
My bloodwork across that six weeks also moved in a direction I was glad to see — lipid markers improved alongside the fat loss itself. I want to be careful here: a calorie deficit and fat loss on their own improve cholesterol markers regardless of what else is in the protocol, so I can't cleanly separate how much of that came from the retatrutide versus the deficit doing what a deficit does. It's one data point from one person, not a controlled comparison. I also noticed I carried the cut better than usual — less of the flat, deflated look a hard deficit usually leaves, though again that's a subjective impression, not a measured outcome.
I'm not covering a protocol or dose here — see the Retatrutide research guide for the mechanism and research data in full. This is a prescription-only GLP-1 medication (see the regulatory note below); nothing here is a recommendation to use it, just what I noticed adding it to an already bloodwork-monitored setup during a genuine deficit.
The Biggest Trial: What TRAVERSE Actually Found
For years the honest answer to "is TRT safe for your heart?" was that nobody had run a trial big enough to say. That changed in 2023. TRAVERSE was a randomised, double-blind, placebo-controlled trial of 5,246 men aged 45 to 80 who had symptoms of low testosterone, two fasting testosterone readings below the reference range, and either existing cardiovascular disease or a high risk of it. Half got a daily transdermal testosterone gel, half got a placebo gel. Mean follow-up was 33 months. It was published in the New England Journal of Medicine: Lincoff AM et al., Cardiovascular Safety of Testosterone-Replacement Therapy, N Engl J Med 2023;389(2):107-117 (PMID 37326322).
The headline result: a major cardiovascular event happened in 7.0% of the testosterone group and 7.3% of the placebo group. Testosterone was non-inferior to placebo on cardiac events. That is the reassuring part, and it is a genuinely important finding given how long the opposite was assumed.
The part that gets left out of the reassuring summaries is the rest of the results. The testosterone group had a higher incidence of atrial fibrillation, acute kidney injury and pulmonary embolism. So the fair reading is not "TRT is safe", it is "TRT did not raise heart attack and stroke risk in a high-risk population, and it did raise some other things you should be monitored for". That is why haematocrit and blood pressure are on my list and not just my testosterone number.
I looked for an Irish cohort study on this and there is not one. The nearest thing to a European read on it is a position statement from the European Expert Panel for Testosterone Research, which reviews TRAVERSE alongside earlier trials and meta-analyses and lands on the same place: reasonable safety in appropriately selected patients, with careful monitoring of haematocrit specifically (Zitzmann M et al., Andrology 2026;14(1):294-302, PMID 40372318).
Two things worth holding on to before anyone reads that as a green light. TRAVERSE enrolled men with diagnosed, symptomatic, biochemically confirmed low testosterone, so it says nothing about a healthy man taking testosterone to train harder. And "non-inferior on cardiac events over 33 months" is not the same as "safe over 30 years". The data is better than it was. It is not finished.
What I'd Tell Someone Considering This
First: bloodwork before anything else. Not a guess, not a feeling — actual numbers. I wrote up why I stopped winging it and test first separately, because it is the single change that made the biggest difference to how I approach any of this. If you're in Ireland, you can access private blood panels without a GP referral — MyBloods.ie is one option I've used for this. Get a full hormone panel including total testosterone, free testosterone, SHBG, LH, FSH, estradiol, and a full lipid profile. That's your baseline. Without it, you have no way of knowing what you're working with or whether anything you do is actually helping.
Second: lowest effective dose is not a limitation, it's a strategy. More is not better here. The goal is to find the minimum dose that gets you to a functional level and keeps you there with stable levels and clean bloodwork. That's it. Anyone pushing you toward higher doses without bloodwork to justify it is not someone whose advice you should be following.
Third: the monitoring schedule matters as much as anything else. Whatever interval your doctor sets, keep it fixed, because trends are the information and you only see a trend if the gaps between draws are the same. Haematocrit in particular is worth watching consistently. An elevated red blood cell count is a real risk with exogenous testosterone, it is one of the few signals the biggest trial in this area actually flagged, and it is easily managed if someone is paying attention to it.
Fourth: address the foundations first. If your sleep is poor, your training is inconsistent, and your nutrition is a mess, TRT is not going to fix those things. It will just mean that your stats look better while those problems continue. In my experience, the people who get the most measurable benefit from TRT are the ones who already have most of the basics in place and are genuinely hitting a ceiling.
Fifth, and it is the filter I put everything through: does this genuinely improve the result enough to justify the health cost, the financial cost, the complexity and the uncertainty? Four costs, not one. Most things fail that question. I went from over 90kg to 72kg on a calorie deficit, enough protein and turning up consistently, and I paid a personal trainer thousands to find that out. Nothing I have added since has done a fraction of what those three did. If the basics are not in place, the answer to the question above is no, and it is no before you even get to the bloodwork.
Summary
TRT is one of the most researched areas in men's health, and also one of the most misrepresented — in both directions. What I've found, through a bloodwork-first, lowest-effective-dose approach over time, is that it's a foundation, not a solution. It creates conditions where consistent effort actually reflects in consistent results. That's worth something, but it only works if the effort is actually there. If you're at the stage of researching this properly, the free tools at nononsensefitness.ie/free-tools are a good place to start. Calculators, a macro planner and a food tracker, all free. No dosing planners, because this site does not publish doses.