RecruitingOBSERVATIONAL

Effects of Obesity on Autophagy and mTORC1 Signalling in Skeletal Muscle

This study aims to understand why people who are overweight or obese might find it harder to build muscle, even when they exercise and eat protein. It's known that muscle growth processes don't activate as strongly in these individuals compared to those who are lean, but the exact reasons inside the muscle cells aren't fully clear. Researchers will compare how muscle cells in lean people and those who are overweight or obese react to a single session of leg exercise and a protein-rich drink. They will take small muscle samples and blood before and after to look at changes at a tiny level. By doing this, they hope to discover specific pathways in muscle cells that could be targeted in the future to help people who are overweight or obese build and maintain better muscle health.

At a glance

Status

Recruiting

Sponsor

University of Birmingham

Enrolment target

Start

15 Apr 2026

Estimated completion

01 Dec 2027

Overweight and Obese Adults

What is this study about?

When we exercise, especially lifting weights, and eat protein, our muscles usually get stronger and grow. However, studies have shown that this process doesn't seem to work as well in people who are overweight or obese, compared to those who are lean. We don't fully understand why this happens at the level of the muscle cells.

This study wants to find out what's different inside the muscle cells of people who are overweight or obese that might prevent them from building muscle effectively. The researchers will ask volunteers to do some leg exercises and drink a protein shake. They will then carefully take small samples of muscle and blood to see how their bodies react. By comparing these reactions between lean individuals and those who are overweight or obese, they hope to identify specific processes that aren't working as well.

Ultimately, the aim is to use this new knowledge to develop better ways to help people who are overweight or obese improve their muscle health. Better muscle quality can help with overall health and make weight loss programs more successful in the long run. This project could pave the way for future treatments or exercise plans that are more effective for everyone.

Key takeaways

This study investigates why muscle growth might be different for people who are overweight or obese.
It compares how muscle cells react to exercise and protein in different groups.
Participation involves one lab visit with exercise, a protein drink, blood tests, and small muscle samples (biopsies).
The goal is to find new ways to improve muscle health and support weight management for others.
You must be 18-45 years old and meet specific weight and health criteria to join.
You can withdraw from the study at any time.

Who may be eligible?

To join this study, you need to be aged between 18 and 45. You'll either need to have a healthy weight (BMI between 18.5 and 24.9) or be considered overweight or obese (BMI above 28). Your weight should have been stable for the last six months, meaning it hasn't changed by more than 5%. You should also be meeting current UK exercise guidelines (at least 150 minutes of moderate activity or 75 minutes of vigorous activity each week), but importantly, you shouldn't have been involved in structured exercise training in the last six months.

There are several reasons why you might not be able to join. For example, if you have certain health conditions like diabetes (especially type 1), thyroid problems, or severe kidney disease, or if you're taking specific medications like anti-diabetes drugs, cholesterol-lowering drugs (statins), or blood thinners. We also can't include you if you're pregnant or breastfeeding, if you're actively trying to lose weight, or if you have any recent leg injuries or tummy problems that affect digestion. If you follow a vegan diet, have allergies to whey protein, or have reacted badly to local anaesthetic before, you also won't be able to take part.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you between 18 and 45 years old?
Is your weight currently stable (no big changes in the last 6 months)?
Do you exercise regularly, but haven't been in a structured training programme for 6 months?
Do you have good general health, without conditions like diabetes, kidney disease, or thyroid issues?
Are you not currently pregnant or breastfeeding?
Do you not have allergies to whey protein or a past bad reaction to local anaesthetic?

Answer every question to see your result.

What does participation involve?

If you decide to take part, you will visit the lab for one main session. During this visit, you will do some resistance exercise with one leg, similar to weightlifting. You will also drink a protein-rich drink. Before and after the exercise and drink, researchers will take several small blood samples and small pieces of muscle from both of your thighs. This involves a procedure called a muscle biopsy, where a tiny piece of muscle is taken out after numbing the area with a local anaesthetic. You will also have a DEXA scan, which is a special type of X-ray that measures your body composition (like how much muscle and fat you have). You will also do some tests to measure your maximum muscle strength. There is no long-term follow-up and the total duration of your involvement will be one lab visit.

Potential risks and benefits

Taking part in this study won't directly improve your health, as it's a research study aimed at understanding a specific process. However, the information gathered could help scientists design better ways to improve muscle health for people who are overweight or obese in the future. Potential risks include discomfort or bruising from blood tests and muscle biopsies, which are minor surgical procedures. You might also feel tired or sore after the exercise. There's a very small risk of infection or nerve damage from the biopsies. You are free to withdraw from the study at any time, for any reason, without it affecting your medical care.

Locations (1)

School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham
Verified postcode
Birmingham, United Kingdom· Recruiting

Common questions

What is a muscle biopsy?

A muscle biopsy is a minor procedure where a small piece of muscle is taken, usually from your thigh, after numbing the area. It helps researchers look at changes inside the muscle cells.

Will this study help me lose weight or get fitter?

This study is for research purposes only and is not designed to directly make you lose weight or become fitter. Its goal is to understand muscle processes to help others in the future.

What is a DEXA scan?

A DEXA scan is a quick and safe scan that uses a very small amount of radiation to measure your body composition, showing how much muscle, bone, and fat you have.

How long will my visit to the lab take?

The study involves one visit to the lab. The exact duration will be explained by the research team, but it will include multiple procedures like exercise, blood draws, and muscle biopsies.

What will happen to my samples?

Your blood and muscle samples will be analysed in a lab to understand the tiny changes happening inside your cells after exercise and the protein drink. Your identity will be kept private.

How to find out more

Jennifer Barrett, PhD

j.s.barrett@bham.ac.uk +447875713844 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.