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
How Exercise Supports Weight Loss
Exercise is a key part of sustainable weight loss, but it works best alongside dietary changes and other lifestyle factors. The NHS recommends combining physical activity with a reduced-calorie diet for effective weight management in the UK. While exercise alone can support weight loss, creating a calorie deficit through both diet and activity produces the most reliable results. Understanding how exercise contributes to your overall weight management strategy helps you set realistic goals and stay motivated.
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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.
The Role of Exercise in Weight Loss
Exercise supports weight loss through several mechanisms. Cardiovascular exercise burns calories during activity, while strength training builds muscle mass, which increases your resting metabolic rate — meaning you burn more calories throughout the day. The NHS recommends at least 150 minutes of moderate-intensity activity per week for adults, such as brisk walking, cycling, or swimming.
- Moderate activity burns approximately 4–7 calories per minute depending on intensity and body weight
- Strength training 2–3 times weekly helps preserve muscle during weight loss
- Regular exercise improves cardiovascular health, blood pressure, and blood sugar control — benefits that extend beyond weight management
- Consistency matters more than intensity — sustainable activity you enjoy is more effective long-term than intense exercise you cannot maintain
For weight management in the UK, the NHS emphasises combining exercise with dietary changes. A calorie deficit of roughly 500 kcal per day (achieved through diet, exercise, or both) typically results in approximately 0.5 kg weight loss per week. Use our free BMI calculator to understand your starting point, then track progress with our progress tracker as you build an exercise routine.
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.
Exercise and Medical Weight Loss Support
If you struggle to lose weight through exercise and diet alone, prescription weight loss medication may be an option. GLP-1 weight loss injections — such as Wegovy or Mounjaro — can support weight management when combined with physical activity and dietary changes. These medications are prescription-only and require a clinical assessment to determine suitability.
Exercise remains important even when taking weight loss medication. Physical activity enhances the benefits of medication, improves cardiovascular fitness, and supports overall health. Our GLP-1 weight loss calculator can help you understand potential outcomes when medication is combined with lifestyle changes. Always consult your GP about the right approach for your individual circumstances — weight management in the UK is most effective when personalised to your health profile and preferences.
- 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.
How much exercise do I need for weight loss?
The NHS recommends at least 150 minutes of moderate-intensity aerobic activity weekly, plus strength training 2–3 times per week. However, any increase in activity helps. Weight loss is most effective when exercise is combined with a calorie deficit through diet. Even 30 minutes of brisk walking daily can meaningfully contribute to weight management.
Can exercise alone cause weight loss?
Exercise alone can cause some weight loss, but results are typically modest without dietary changes. Creating a calorie deficit requires burning more calories than you consume — most people find this easier by combining both reduced calorie intake and increased activity. The NHS emphasises that diet and exercise together produce better outcomes than either approach alone.
What type of exercise is best for weight loss?
Both cardiovascular exercise (walking, cycling, swimming) and strength training are valuable. Cardio burns calories during activity, while strength training builds muscle, which increases your resting metabolic rate. A combination of both, done consistently, is most effective. Choose activities you enjoy so you can maintain them long-term.
Does exercise burn enough calories for weight loss?
Exercise burns calories, but the amount varies by activity intensity and body weight. A 70kg adult might burn 250–400 calories in 30 minutes of moderate exercise. However, creating a calorie deficit through diet is often more efficient than relying on exercise alone. Most weight loss experts recommend combining reduced calorie intake with regular physical activity for best results.
Can I take weight loss injections and still exercise?
Yes — prescription weight loss medications like Wegovy or Mounjaro work alongside exercise and dietary changes, not instead of them. In fact, combining medication with physical activity typically produces better outcomes. Always discuss your exercise plan with your GP or prescriber to ensure it is safe and appropriate 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.