Exercise While on Semaglutide: A Real-World Guide
- Michael Dilworth
- Dec 13, 2025
- 7 min read
You’re standing in front of the mirror. The scale is finally moving down. Your clothes are looser. But you also feel… weaker. Softer. A little unsteady on your feet.
I’ve talked to a lot of people in exactly that spot. I’m Coach Michael, a personal trainer and corrective exercise specialist. I’m also a spinal-fusion survivor, but this article isn’t about surgery, it’s about what happens when you use powerful weight-loss meds like semaglutide and don’t have a plan for your strength.
Quick note before we dig in:
This article is for education only. I’m not a doctor, and this is not medical advice. Any decisions about medications, side effects, or big changes to your exercise routine, especially if you have medical conditions or past surgeries, need to be cleared with your doctor.
I want to talk about what the research says about semaglutide, and what I’ve actually seen on the gym floor with real people.
“I’ll Start the Gym After the Shots Work…” (A Common Trap)
One conversation sticks with me.
A very overweight man told me, “I’m going to stay on the shots until I lose a bunch of weight. Then I’ll come see you for training.”
On paper, that sounds reasonable. Lose weight first, then “tone up.” But in real life, that’s backwards.
In most members and clients I’ve seen on GLP-1 shots, the pattern looks like this:
They lose a lot of weight fast.
They’re thrilled with the number on the scale.
They arrive at the gym later feeling weaker, “deflated,” sometimes lightheaded or unwell.
Their legs, arms, and back muscles look and feel noticeably smaller.
The shots did their job. But without exercise while on semaglutide, the body often gives up muscle along with fat, and possibly even some bone robustness. I don’t have direct lab data on bone density from my clients, but when someone loses weight quickly, doesn’t lift, and comes in feeling fragile, my coaching alarm goes off.
That’s why I don’t want you to wait until “after the shots work” to start training. I want you building strength the entire time.
What the Semaglutide Study Actually Showed
Big Weight Loss, But Not the Whole Story
In this study, nearly 2,000 adults with overweight or obesity were followed for 68 weeks.[1] All participants were asked to:
Eat fewer calories (about a 500 kcal/day deficit)
Aim for at least 150 minutes per week of physical activity
Attend regular lifestyle counseling
Half the group got once-weekly semaglutide injections. The other half got placebo injections.[1]
After about a year and four months:
Other trials show that people can keep a lot of that loss for up to two years if they stay on the medication and keep working on habits.[2,3]
So yes, these meds are strong tools. They do what they’re supposed to do: help you eat less and lose weight.
What the paper did not focus on in detail was how much of that weight loss came from muscle versus fat, or what happened to bone density.[1] That’s where real-world experience, and smart training, matter.
Where My Coaching Experience Lines Up, and Where It Doesn’t
Where the research and my experience match:
Weight loss is often dramatic.
People report feeling physically “lighter” and seeing improved lab markers.
Many say daily tasks feel easier in some ways.
Where my coaching experience adds a warning sign:
Most people I meet who’ve been on semaglutide and didn’t lift weights during that time describe:
Feeling weaker, especially in their legs and grip
Having more trouble getting up from the floor or off low chairs
Sometimes feeling dizzy or “drained” when they finally start working out
Concern about loose skin and a “flat” look, not the firm, strong body they imagined
That doesn’t mean the medication is bad. It means that medication alone doesn’t build an ideal body. And fast weight loss without strength work often means a smaller body that’s easier to move, but less equipped to handle life.
Why Exercise While on Semaglutide Matters So Much
Muscle, Bone, and the “Smaller but Weaker” Problem
Any major weight-loss plan, surgery, strict dieting, or GLP-1 meds carries a risk: losing muscle along with fat.[2,3]
If you’re over 35 or 40, you’re already fighting age-related muscle loss. Add rapid weight loss and no strength training, and the “shrinkage” can hit your muscles and, over time, your bones.
From what I’ve seen with clients:
Thighs and glutes get smaller but weaker.
Arms lose size and strength, making lifting and carrying harder.
Balance feels more insecure, especially on stairs or uneven ground.
I also have concerns about bone health in some people, especially if they’re moving less, eating less, and not loading their skeleton with resistance. I want to be clear: that concern is based on coaching patterns and general principles of bone health, not something that was measured in this study.[1]
How This Affects Your Back, Joints, and Daily Life
Less muscle around your hips, core, and shoulders means:
Your back has less support.
Your knees and hips may take more direct stress.
Your neck and shoulders can feel tighter and more overworked.
In the study, participants reported improvements in physical functioning with semaglutide.[1] I see some of that in real life too, but I also see people who are lighter and still nervous to bend, lift, or carry because they feel wobbly.
The goal isn’t just a smaller body. The goal is a body you trust. That’s where your training plan comes in.
Building a Realistic Exercise Plan While on Semaglutide
Start Simple: Walking and Basic Movement
If you’re new to movement or coming back after a long break, start smaller than you think:
Short walks (5–10 minutes) a few times per day
Light household movement: carrying laundry, light cleaning, taking the stairs once or twice
Gentle mobility drills for hips, shoulders, and upper back
For many of my clients on semaglutide, just committing to regular walking and a few basic movements is a huge win. This absolutely counts as exercise while on semaglutide.
Add Strength Training 2–3 Days a Week
To protect muscle, you’ll want 2–3 strength sessions per week, 30–45 minutes each. Focus on simple patterns, not fancy exercises:
Squat / Sit-to-Stand: From a chair or bench, stand up and sit down under control.
Hip Hinge: Light deadlift-like motion with a kettlebell or dumbbells, keeping your back neutral.
Push: Wall or incline push-ups, light dumbbell presses.
Pull: Band rows or cable rows.
Carry: Farmer’s carries with light weights as tolerated.
The goal is not to destroy yourself. It’s to give your muscles and bones a clear message: “We still need you. Don’t go anywhere.”
If you have back pain or a sensitive spine, we can still use these patterns; we just scale them, keep the load modest, respect your range of motion, and progress gradually.
Adjusting for Nausea, Fatigue, and “Off” Days
Many GLP-1 users report nausea, diarrhea, or general fatigue, especially in the early stages or after dose changes.[1–3] I’ve seen this play out with clients who suddenly hit a “wall” mid-session or show up pale and uneasy.
On those days:
Shorten the session; focus on walking, light mobility, and easier sets.
Avoid intense core work or heavy bending if your stomach feels unstable.
Keep water handy, and don’t train right at peak nausea if you can help it.
Keep your doctor in the loop about side effects, they’re the ones who manage medication decisions, not your trainer.
A smart plan has room for dialed-down days instead of all-or-nothing thinking.
Where to Start: A Simple Action Plan
You don’t need a perfect program. You need something you’ll actually do. Here’s a starting point you can tweak with a qualified coach:
Where to Start – Action Plan
1. Commit to Walking: Choose a realistic goal like 10 minutes of walking, 4–5 days per week. It can be split into small chunks.
2. Schedule Two Strength Days: Pick two non-consecutive days (for example, Tuesday and Friday) for simple full-body strength: squat/sit-to-stand, hinge, push, pull, and a bit of core/balance.
3. Protect Muscle and Joints: Focus on slow, controlled reps and a weight that feels “medium challenging” rather than extreme. Your joints and back will thank you.
4. Eat Enough Protein (Within Your Medical Plan): Talk with your healthcare provider about a protein target that fits your health picture, so your muscles have the raw materials they need while your appetite is lower.[3]
5. Track More Than Weight: Every 4–6 weeks, note how it feels to stand up, climb stairs, carry groceries, and walk. Those changes matter as much as the number on the scale.
Gentle Next Steps if You Want Help
I’ve seen what happens when people rely on the shots alone: smaller bodies that sometimes feel weaker, more fragile, and scared in the gym. I’ve also seen what happens when they use medication and training together: lighter bodies that move better, feel stronger, and handle life with more confidence.
If you’re using semaglutide, or thinking about it, and you’re unsure how to protect your muscle, joints, and long-term health, you don’t have to figure it out alone.
You can:
Save this article to revisit as you go through your journey.
Share it with your doctor and ask how exercise fits with your plan.
Consider working with a coach who understands midlife bodies, fear of injury, and the reality of training while on GLP-1 medications.
If you’d like support building a plan that respects your history, your energy levels, and your goals, you can book a consultation. We’ll build a step-by-step program so the shots don’t just make you smaller, they help you become stronger, steadier, and more at home in your body.
Reference
[1] Wilding JPH, Batterham RL, Calanna S, et al. Once-weekly semaglutide in adults with overweight or obesity. New England Journal of Medicine. 2021;384(11):989–1002. doi:10.1056/NEJMoa2032183. https://www.nejm.org/doi/full/10.1056/NEJMoa2032183
[2] Garvey WT, Batterham RL, Bhatta M, et al. Two-year effects of semaglutide in adults with overweight or obesity: the STEP 5 trial. Nature Medicine. 2022;28(10):2083–2091. doi:10.1038/s41591-022-02026-4. https://pubmed.ncbi.nlm.nih.gov/36216945/
[3] Qin W, He S, Wang H, et al. Efficacy and safety of semaglutide 2.4 mg for weight loss in overweight or obese non-diabetic individuals: a systematic review and meta-analysis. Diabetes, Obesity and Metabolism. 2024;26(1):xx–xx. doi:10.1111/dom.15011. https://pubmed.ncbi.nlm.nih.gov/38016699/