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
Best Fitness for Weight Loss — Evidence-Based UK Guide
The best fitness for weight loss combines cardio, strength training, and consistency — but exercise alone rarely achieves significant weight management. In the UK, the NHS recommends combining regular physical activity with dietary changes and, where appropriate, weight management support. Your fitness routine should be sustainable, progressive, and matched to your current BMI and health status. Use our free BMI calculator to understand your starting point, then work with your GP to create a personalised plan that includes both exercise and nutrition.
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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.
Types of Fitness That Support Weight Loss
Cardiovascular exercise (running, cycling, swimming, brisk walking) burns calories during activity and improves heart health. Aim for at least 150 minutes of moderate-intensity cardio per week, or 75 minutes of vigorous activity, according to NHS guidelines. Strength training (weights, resistance bands, bodyweight exercises) builds muscle mass, which increases resting metabolic rate — meaning you burn more calories even at rest. Include 2–3 strength sessions weekly. Combination training alternates between cardio and strength work within sessions, maximising calorie burn and fitness gains. Research shows that combining these approaches produces better weight loss results than cardio alone. For nhs weight loss programmes in your area, ask your GP about tier 3 specialist weight management services that often include exercise advice.
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.
Why Exercise Alone May Not Be Enough
Even regular fitness cannot overcome a poor diet — weight loss fundamentally requires a calorie deficit, typically achieved through reduced calorie intake. The NHS notes that weight management uk services recommend combining diet, exercise, and behavioural support for best results. For some people, prescription weight loss uk options like GLP-1 medications (Mounjaro or Wegovy) may be appropriate alongside fitness. These work by reducing appetite and supporting portion control, making calorie deficits more sustainable. Our GLP-1 weight loss calculator can help you explore potential outcomes when combining medication with exercise and diet. Always consult your GP before starting new fitness routines or considering medication.
- 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.
What is the best type of exercise for losing weight?
A combination of cardiovascular exercise (150 minutes per week) and strength training (2–3 sessions weekly) is most effective. Cardio burns calories during activity; strength training builds muscle, which increases your resting metabolic rate. The NHS recommends combining both for sustainable weight loss results.
How quickly will fitness help me lose weight?
This depends on exercise intensity, duration, diet, and current BMI. A typical calorie deficit through exercise and diet produces about 0.5–1 kg weight loss weekly. Use our BMI calculator to track your starting point and monitor progress with our free progress tracker.
Can I lose weight through exercise without changing my diet?
Rarely significantly. Weight loss requires a calorie deficit, primarily achieved through eating less. Exercise supports this by burning additional calories and improving fitness, but diet changes are usually the main driver of weight loss. Most effective approaches combine both.
Is walking enough exercise for weight loss?
Brisk walking counts as moderate-intensity cardio and contributes to calorie burn, especially if done consistently (30 minutes daily). However, adding strength training and increasing intensity typically produces better weight loss results than walking alone.
Should I do fitness before starting weight loss medication like Wegovy?
No — you can start fitness immediately. In fact, combining regular exercise with prescription weight loss medication produces better long-term results than either alone. Your prescriber will advise on the best approach for your individual health situation.
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.