A client tells you they have started semaglutide, or their weight drops four kilos in a fortnight and you work out why. The weight is coming off faster than anything you have programmed, most of what you normally do to create a deficit is now irrelevant, and the client is eating a third of what they were.
You are not going to talk them out of it and it is not your call anyway. What you have to decide is what your coaching is actually for now, because "hit these calories" stopped being the job the day the prescription started.
Where your job starts and stops
GLP-1 receptor agonists — semaglutide, tirzepatide and the others in the class — are prescription medicines. In Australia they are Schedule 4, prescribed and monitored by a doctor after a clinical assessment, and everything about the drug itself belongs to that doctor. Not to you, not to the client's group chat, and not to whatever the client read on TikTok.
That line is not a legal formality you nod at in the onboarding form. It is the thing that decides what you say when a client messages you at 9pm saying the nausea is unbearable and should they skip this week's dose.
| Yours | The prescriber's |
|---|---|
| Protein target and how the client hits it | Whether to be on the medication at all |
| Resistance training and progression | Dose, titration and timing |
| Tracking body composition, not just weight | Managing side effects |
| Sleep, steps, hydration, habits | Whether to pause, reduce or stop |
| Noticing symptoms and telling them to call the doctor | Bloods, comorbidities, interactions |
| The plan for after the medication | Anything involving the words "should I" |
The answer to that 9pm message is: I can't advise on the medication, ring your prescriber, and here is what we are doing with training and food in the meantime. Say it in the same words every time. Clients who like you will try to make you the expert on everything, and this is the one area where being helpful is the mistake.
The same discipline applies to any medically managed client — the scope section in coaching clients through menopause is the same argument about a different prescription.
What changes the day the client starts
The medication works partly by slowing how fast the stomach empties and partly by acting on the brain's appetite signalling. The practical result is that the client is full sooner, stays full longer, and often stops finding food interesting. Energy intake falls without them deciding anything.
That inverts your normal problem. For years your job has been helping people eat less than they want to. Now the deficit arrives on its own, it is often much larger than you would ever have prescribed, and your job is making sure the food they do eat is the right food.
Three things follow immediately:
- Calorie targets stop driving behaviour. A client who cannot finish a meal is not going to be moved by a lower number. If they are undereating badly you may be raising the target, not lowering it.
- Protein becomes the only intake number worth coaching to. More on this below, because it is the whole article.
- Everything you would normally do at the end of a long diet — checking energy, sleep, training performance, mood — you do now, from week one. The rate of loss is doing what a very aggressive deficit does, without the client having to be disciplined about it.
Protein is the number that matters now
When someone loses weight quickly, some of what comes off is lean tissue. That is true of any large deficit, medication or not. Two things reduce how much: eating enough protein, and giving the muscle a reason to stay. Those are both squarely your job, and on a GLP-1 they are close to the entire job.
The ranges most coaches work from do not change because of the medication — a client in a deficit holding muscle sits around 2.0–2.4 g/kg, and a client with a lot of fat to lose is better calculated on goal weight at 1.6–2.0 g/kg. The reasoning behind those numbers is in how to set protein targets. What changes is that the target has become genuinely hard to eat, and a target the client misses by 40 g every day is not a target, it is a number in your software.
So set it, then coach the gap. If your client is landing at 90 g against a target of 140 g, the useful work is not restating the 140. It is finding four separate places in the day where 15 g can go in without a meal happening.
How to hit protein when nothing appeals
This is the practical centre of coaching a client on these medications, and it is unglamorous. The constraint is volume — they physically cannot get through a plate of food — and often texture, because meat in particular becomes unappealing for a lot of clients. So the answer is protein that is dense, liquid or soft.
| Constraint | What it looks like | What works |
|---|---|---|
| Cannot finish a meal | Half a plate left, every time | Eat the protein first, before anything else on the plate |
| Nothing appeals at all | Skipping meals entirely | Liquid protein — shakes, milk, drinking yoghurt |
| Meat has gone off them | Chicken and steak untouched | Eggs, dairy, fish, tofu, legumes, protein powder |
| Full after two bites | Three meals is unrealistic | Four or five small protein occasions, not meals |
| Mornings are worst | Nausea early, better by evening | Front-load nothing; put the protein where the appetite is |
Four rules that hold across most clients:
Protein first, every time. If they only get through 40% of the plate, that 40% should be the chicken and not the rice. This one instruction does more than any target adjustment.
Stop calling them meals. A client who cannot face dinner can often manage a Greek yoghurt. Reframe the day as four or five protein occasions and the number becomes reachable.
Use liquids without apology. Shakes, milk, high-protein yoghurt drinks. Whole food is better in principle and irrelevant if it does not get eaten.
Track for two weeks, then stop. You need to know where they actually land, not what they intend. Once you both know the pattern, daily tracking on a suppressed appetite becomes another thing to fail at. Get the data, fix the structure, then track protein only.
Watch total intake too. Some clients drift to 700 calories a day without noticing, and that is a conversation with the prescriber, not a target you quietly accept because the scale is moving.
Resistance training is the other half
Protein without training is half a strategy. Muscle that is not being used is the first thing the body is willing to give up, and lifting is the signal that stops it.
For a client on a GLP-1, resistance training is the non-negotiable part of the week and cardio is the optional part. If time or energy is limited, cardio gets cut first — reverse the priority you might use with a client who is not losing weight this fast.
What that looks like in practice:
- Two to four full-body or upper/lower sessions a week, hitting everything. Not a leg day they skip when they feel flat.
- Keep the load. Weight on the bar is the signal. When appetite is suppressed and energy is low, the instinct is to drop weight and add reps — resist it. Fewer sets at the same load beats the same sets lighter.
- Progress conservatively. You are not going to add strength quickly in a large deficit. Holding position is a win, and you should tell the client that before they interpret a flat log as failure.
- Steps stay in. They are cheap, they do not need recovery and they keep the client moving on days when a session is not happening.
Training around the low days
Some days the client will have nothing. Not laziness — the combination of a very low intake and the side effects flattens people, and it can be worst in the days after a dose increase.
Have a rule ready before it happens, so the choice is not made at 6am in bed. The one that works: the session gets shortened, not cancelled. Two compound lifts, top sets only, out in twenty minutes. A client who trains at 40% on a bad day keeps the habit and the muscle signal. A client who skips has now missed one session and made missing the next one easier.
If the low days are most days, that is not a programming problem. That is information for the prescriber.
The scale looks great and the composition may not
The weight will drop faster than anything you have produced before, and the client will be delighted. This is the point where a coach who only tracks weight has no idea what is actually happening.
You need something that separates fat loss from everything else. Weekly weight is still worth taking, but on its own it is now the least informative number you have. What tells you more:
- Progress photos on a fixed schedule. Same lighting, same time of day. Over eight weeks they show what the scale cannot.
- Circumference measurements. Waist, hips, thigh, arm. Cheap, and the arm and thigh numbers are the ones to watch — if they are falling as fast as the waist, you have a problem.
- The training log. Strength holding on a large deficit is decent evidence the muscle is still there. A steady slide across every lift, with protein and sessions on track, is not.
- How they look and feel at the same weight. The client who has lost 12 kg and cannot carry the shopping has not got what they came for.
This is the same measurement problem as coaching a client through body recomposition — the scale is not answering the question, so stop asking it. The difference is that here the scale is going to give you a flattering answer for months, which makes it much easier to ignore the numbers that matter.
What the check-in should ask
The standard check-in was built for a client trying to eat less. It asks about adherence, hunger and whether they hit their calories. Half of that is now noise.
The questions worth asking a client on a GLP-1:
- Protein hit, in grams, most days — yes or no.
- Sessions completed, and whether the loads held.
- Energy through the day, on a simple one-to-five scale.
- Anything new physically, in their own words.
- Waist and one limb measurement, plus photos every four weeks.
A recurring check-in form with rating scales, body-metric fields and progress photo questions will collect all of that on a schedule, and the metric answers land on the client's profile so you can see the trend rather than scrolling back through submissions.
That fourth question is the important one. You are not diagnosing anything and you should not try. You are the person who sees this client every week, which means you may be the first to notice that the fatigue has become something else, or that they have barely eaten in five days. When something in that answer sounds wrong, the response is the same every time: that is one for your doctor, ring them this week. Then note that you said it.
When the client credits the drug and not the coaching
Here is the retention problem. The weight is falling, the client believes the medication is doing it, and by month four they are wondering what they are paying you for.
They are half right, which is why the answer has to be honest rather than defensive. The medication is producing the weight loss. What your coaching produces is what they weigh at the end, what the weight is made of, and whether any of it stays off. Say that out loud in the first month, before the results arrive and the question forms on its own. Clients who cannot name what your service is doing for them cancel it — that is most of why coaching clients quit, and here the trigger is predictable enough that you can get ahead of it.
The concrete version: report on the things you are responsible for. Strength held across a 15 kg loss. Waist down 11 cm while the arm measurement barely moved. Protein averaging 130 g on an appetite that would default to 60. Those are your results and they are visible in the data you are already collecting, if you have been collecting the right data.
Coaching for the day they come off
Most clients do not stay on these medications forever. Cost, side effects, supply, or their doctor decides the course is done. When the appetite comes back — and it does — the client is back to managing their own intake with whatever eating skills they have.
That is the coaching job hiding inside this entire arrangement, and the window to do it is while they are still on the medication. A client who spent a year on a suppressed appetite and never learned to build a meal has been handed a much harder problem than the one they started with.
While intake is low, teach the structure they will need later:
- What a meal is built from. Protein, a carbohydrate, vegetables, a fat source. When the appetite returns, they should already know the shape of the plate.
- Portion sizes by eye. They are not going to weigh food forever, and right now the stakes of getting it wrong are low.
- A repeatable weekly routine. Same shop, same handful of meals, same training days. Routine is what holds when motivation and appetite both change.
- Eating that is not driven by the drug. Regular timing, protein at every occasion, not skipping because nothing appeals.
Structurally this is habit work, not nutrition work — small, specific, tracked behaviours rather than targets, which is the whole method in habit coaching for fitness clients.
Expect some regain when they stop, tell them so early, and make the plan for it while everything is still going well. The muscle they kept and the routine they built are what decide how much comes back. Both of those are yours.
