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
Does Exercise Help With Weight Loss?
Yes, exercise absolutely helps with weight loss, but it works best alongside dietary changes. Physical activity burns calories, builds muscle, and improves metabolic health — all essential for sustainable weight management. However, exercise alone without calorie reduction typically produces modest results. The most effective weight loss approach combines increased physical activity with a reduced-calorie diet. For some people in the UK, prescription weight loss medication may also support this process under medical supervision. Understanding how these factors work together helps you achieve better outcomes.
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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 Exercise Supports Weight Loss
Exercise contributes to weight loss in several ways. First, it burns calories during the activity itself — the amount depends on the intensity, duration, and your body weight. Second, regular physical activity builds lean muscle mass, which increases your resting metabolic rate (the calories you burn at rest). Third, exercise improves insulin sensitivity and blood sugar control, supporting better overall metabolic health. Fourth, physical activity has psychological benefits: it reduces stress, improves mood, and can help reduce emotional eating. According to NHS guidance, adults should aim for at least 150 minutes of moderate-intensity aerobic activity weekly, plus strength training twice weekly. Research shows that combining exercise with dietary changes produces significantly better weight loss results than either approach alone. For weight management in the UK, GPs often recommend this combined lifestyle approach as the foundation before considering prescription weight loss medication.
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 Alone vs. Diet Plus Exercise
Studies consistently show that exercise alone produces slower weight loss than calorie reduction alone. However, combining both creates the most effective and sustainable results. A typical calorie deficit of around 500 kcal per day — achieved through both reduced food intake and increased activity — supports a loss of approximately 0.5 to 1 kg per week according to NHS recommendations. Exercise prevents muscle loss during weight loss, which is crucial for maintaining a healthy metabolism long-term. Additionally, regular physical activity reduces health risks associated with excess weight, including type 2 diabetes and cardiovascular disease, independent of weight loss itself. For people using weight loss injections in the UK like GLP-1 medications, exercise amplifies results and improves overall fitness beyond what medication alone achieves.
- 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 to lose weight?
The NHS recommends at least 150 minutes of moderate-intensity aerobic activity per week (such as brisk walking or cycling) plus two sessions of strength training. However, even modest activity is beneficial. The exact amount varies by individual fitness level. Consult your GP for personalised guidance based on your current health.
Can I lose weight with exercise alone?
Exercise alone produces slower weight loss than combining exercise with a reduced-calorie diet. Most people need a calorie deficit to achieve significant weight loss. Aim for a 500 kcal daily deficit through both dietary changes and increased physical activity for optimal results.
What type of exercise burns the most calories?
High-intensity interval training (HIIT), running, and cycling burn the most calories per minute. However, any regular activity is valuable — walking, swimming, and strength training all support weight loss. Choose activities you enjoy so you'll stick with them long-term.
Does exercise help with prescription weight loss medication?
Yes, absolutely. Exercise enhances results from medications like GLP-1 weight loss injections. Physical activity improves fitness, prevents muscle loss, and supports better overall health outcomes beyond what medication alone achieves. Always combine medication with lifestyle changes.
How long before exercise helps with weight loss?
You may notice improved fitness and energy within 2–4 weeks of regular exercise. However, visible weight loss typically takes 4–8 weeks alongside dietary changes. Use our free BMI calculator to track your progress and our progress tracker to log your activity and weight changes over time.
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.