The UK's most complete GLP-1 guide
Every Question Answered. Every Side Effect Explained.
- How GLP-1 medications work
- Mounjaro vs Wegovy compared
- Injection instructions
- Side effects & solutions
- What to eat on treatment
- FAQs answered
Free tracker included with every download this week
Weight Loss Programs and Gym-Based Fitness Approaches
Combining gym-based exercise with a structured weight loss program is one of the most effective approaches to losing weight sustainably in the UK. Whether you're looking to manage your weight through fitness alone or alongside prescription weight loss medication, understanding your options—from NHS weight management programmes to private gym memberships—can help you choose the right path. Our free BMI calculator can help you establish your starting point, while many people find that combining exercise with dietary changes produces the best long-term results.
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Calculate Your BMI Instantly
Enter your height and weight below. Supports both imperial (stone & lbs) and metric (kg). Results include NHS category, healthy weight range, and ethnicity adjustments.
What Is BMI and Why Does It Matter?
Body Mass Index (BMI) is the most widely used screening tool for assessing whether your weight falls within a healthy range. Used by the NHS, GPs, and weight management services across the UK, BMI provides a quick snapshot of your weight relative to your height. The formula is simple: your weight in kilograms divided by your height in metres squared (kg/m²).
While BMI isn't a perfect measure — it doesn't account for muscle mass, bone density, or fat distribution — it remains the standard first step in identifying potential weight-related health risks including type 2 diabetes, cardiovascular disease, high blood pressure, and certain cancers.
The NHS also recommends adjusted thresholds for people of South Asian, Chinese, or Black African heritage — a BMI of 23 or above is classified as overweight, and 27.5 as obese. Our calculator includes this adjustment as a one-click toggle.
How Gym Exercise Supports Weight Loss
Exercise is a key component of any successful weight loss programme. The NHS recommends at least 150 minutes of moderate-intensity aerobic activity per week for adults, alongside strength training twice weekly. Gym-based workouts help in several ways: they create a calorie deficit when combined with reduced-calorie eating, build muscle (which increases your resting metabolic rate), improve cardiovascular health, and support mental wellbeing—all crucial for sustainable weight management.
Different gym activities suit different needs. Cardiovascular exercise like running, cycling, or rowing burns significant calories during the session. Resistance training preserves muscle during weight loss, which is particularly important because muscle tissue is metabolically active. Many people find that combining both types of exercise—cardio and strength work—produces better results than either alone.
The key is consistency. A structured gym programme with regular attendance, progressive challenges, and variety helps maintain motivation and prevents plateaus. For UK adults managing their weight, combining gym attendance with NHS weight management guidance or evidence-based nutrition planning typically produces the most sustainable outcomes.
Clinically BackedWeight Loss
No appointments. No waiting rooms. Just care — from a UK-regulated online pharmacy.
How It Works
Three simple steps to understand your weight and take action.
Enter your height and weight in our free calculator. Get your BMI, NHS category, healthy weight range, and ethnicity-adjusted thresholds instantly.
If your BMI suggests you're overweight or obese, explore our GLP-1 calculators to project potential weight loss on Mounjaro or Wegovy.
Use our progress tracker to log your weight weekly, visualise your journey with charts, and stay motivated — all stored privately in your browser.
Free Weight Loss Tools & Guides
Everything you need to understand your weight, explore medication options, and track your progress — completely free.
Weight Loss Programs in the UK — What's Available
The NHS offers tier 1 and tier 2 weight management services in most areas, which include group-based behaviour change programmes often delivered in community settings. These typically combine exercise guidance with dietary advice and psychological support. For more intensive support, NHS tier 3 specialist services may include access to prescription weight loss medication alongside supervised exercise and nutrition plans.
Private weight loss programmes range from commercial chains (such as gym-based memberships with nutrition plans) to online coaching services combining fitness, nutrition, and progress tracking. Many people use our free progress tracker to log their gym attendance and weight changes alongside diet to stay accountable.
For those managing obesity or struggling with weight loss through exercise and diet alone, prescription weight loss medication alongside gym attendance may be appropriate. These work best as part of a comprehensive approach rather than a replacement for lifestyle changes. Consulting your GP about what option suits your circumstances is the first step.
- Dual GIP/GLP-1 receptor agonist
- Up to 22.5% body weight loss (SURMOUNT-1)
- Weekly injection, dose escalation over 20+ weeks
- Available via private prescription in the UK
- Doses: 2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg
- GLP-1 receptor agonist
- Up to 15–17% body weight loss (STEP trials)
- Weekly injection, 5-step dose escalation
- NHS & private prescription available
- Doses: 0.25mg → 0.5mg → 1mg → 1.7mg → 2.4mg
Mounjaro vs Wegovy: Head-to-Head
A side-by-side comparison of the two most popular GLP-1 weight loss medications available in the UK.
| Feature | Mounjaro | Wegovy |
|---|---|---|
| Drug class | Dual GIP/GLP-1 agonist | GLP-1 agonist |
| Active ingredient | Tirzepatide | Semaglutide |
| Avg. weight loss | 15–22.5% | 12–17% |
| Key trial | SURMOUNT-1 (2022) | STEP 1 (2021) |
| Max dose | 15 mg weekly | 2.4 mg weekly |
| Escalation period | 20–32 weeks | 16–20 weeks |
| Administration | Weekly injection (pen) | Weekly injection (pen) |
| NHS availability | Private prescription only | NHS & private |
| Approx. private cost | £150–£250/month | £150–£300/month |
| Common side effects | Nausea, diarrhoea, constipation | Nausea, vomiting, diarrhoea |
Data sourced from SURMOUNT-1 and STEP 1 clinical trials. Costs are approximate and vary by provider. Always consult a prescriber.
Am I Eligible for Weight Loss Medication?
In the UK, eligibility for GLP-1 weight loss medications like Mounjaro and Wegovy is based on your BMI and overall health profile.
- BMI of 30 or above (obese)
- Age 18 or over
- No contraindicated conditions
- Committed to lifestyle changes
- BMI of 27 or above
- Plus type 2 diabetes
- Or high blood pressure
- Or obstructive sleep apnoea
Use our BMI calculator to check whether your BMI falls within the eligible range.
How We Built These Tools
Every calculator and guide on myweightcheck is built with accuracy and transparency in mind. Our BMI calculator uses the standard WHO formula with NHS-aligned category thresholds. Our GLP-1 projections are modelled on published clinical trial data from SURMOUNT and STEP studies.
All data stays on your device. We don't require sign-ups, and we don't store your health information on any server. Your progress tracker saves data locally in your browser using localStorage, so only you can see it.
We're based in the UK and our tools are designed specifically for UK users — supporting stone & lbs by default, referencing NHS guidelines, using NICE-approved medication data, and linking to GPhC-registered pharmacies.
Frequently Asked Questions
Common questions about BMI, weight loss medications, and our free UK tools.
Can I lose weight through gym exercise alone without changing my diet?
Weight loss primarily depends on creating a calorie deficit, so exercise alone can work—but diet changes typically produce faster, more sustainable results. Most evidence suggests combining exercise with a reduced-calorie diet is most effective. The NHS recommends both for best outcomes.
What's the difference between NHS weight loss programmes and private gym memberships?
NHS programmes (tiers 1–3) are free, multidisciplinary services combining exercise guidance, nutrition, behaviour change support, and potentially prescription medication. Private gym memberships focus primarily on fitness access. NHS specialist tier 3 services may include prescription weight loss support alongside exercise.
How often should I go to the gym for weight loss?
The NHS recommends 150 minutes of moderate-intensity aerobic activity weekly plus strength training twice weekly. Most people achieve this with 3–5 gym sessions per week. Consistency matters more than intensity—a sustainable routine beats sporadic intense sessions.
Can prescription weight loss medication replace gym exercise?
No. GLP-1 weight loss medications like Mounjaro or Wegovy work best alongside exercise and dietary changes, not instead of them. They support appetite regulation but don't replace the health benefits of physical activity. Always combine medication with lifestyle changes.
What should I do if I'm not losing weight despite going to the gym?
First, check your calorie intake—exercise alone won't create sufficient deficit without dietary adjustment. Use our free BMI calculator to track progress. If you've plateaued after 8–12 weeks despite consistent effort, speak to your GP about whether prescription weight loss treatment might support your gym efforts.
Ready to take control of your weight loss journey?
Start with a free BMI check, explore your GLP-1 options, or begin tracking your progress today. No sign-up. No cost. Just results.