Trial · Interventional
RecruitingNot applicableRegistry dataShort name FLEX
This trial does not test a peptide that PepBank tracks.
United Kingdom
1 trial · 1 ongoing
Text and fields below are the sponsor's entries at ClinicalTrials.gov, shown as posted.
This study aims to investigate the effect that a structured, progressive resistance exercise program may have on maintaining the muscle mass and physical function of overweight/ obese females whilst they experience a tirzepatide (GLP-1/GIP receptor agonist) induced weight loss. Overweight and obese females aged 25-50 will be recruited for the study, they will require a BMI of \>30 or \>27 with one obesity related comorbidity (excluding diabetes). They will be screened, prescribed tirzepatide and then randomly assigned to either the intervention (GLP-1/GIP + Exercise) or the control group (GLP-1/GIP). Groups will then be split into pre and peri menopausal groups to provide a further exploratory pathway looking analysing if the menopause transition may have any effect on our outcome variables. This was proposed as in the UK females are more likely to begin GLP-1RA treatment. Both groups will be given an industry standard treatment of tirzepatide over 20 weeks starting at a dose of 2.5mg/week and following the dose titration process of +2.5mg/week every four weeks outlined by its manufacturers. The Exercise Group (GLP-1 +EXC) will be given the same tirzepatide prescription alongside following a progressive resistance exercise program. The exercise program will follow a similar structure to previous work in which participants will complete a propriety 20-wk whole body, low impact resistance exercise training program four times a week. The exercise sessions will be up to an hour and will be instructor lead by video and supervised by a member of the research team at The University of Exeter.
Experimental
GLP-1RA+EXERCISE
In the resistance exercise arm participants will undergo a 20 week resistance exercise program. This will be s supervised in person session 4 times a week.
Placebo comparator
GLP-1RA
Habitual physical activity guidelines
Outcomes the sponsor listed as primary.
Skeletal Muscle Mass
Time frame · Skeletal muscle mass will be plotted over time and we will compare the pre , mid and post values (weeks 0, 10 and 20) to see if there was a change in both groups.
Muscle Mass via (D3-Creatine). Skeletal muscle mass will be measured by the stable isotope labelled tracer creatine technique using methyl-\[D3\]-creatine (D3-Cr) to quantify whole-body skeletal muscle mass. A fasted urine sample will be collected after which a 30mg of D3-Cr will be administered at hr 0s. Total 24 hr urine volume output will be collected by the participant and returned to laboratory for analysis. Single urine samples will also be collected at 48 and 72 hrs after D3-Cr ingestion.
Muscle Thickness (Ultrasound)
Time frame · Muscle thickness in millimetres will be plotted over time (week 0, 4, 8, 10, 12, 16, 20) and compared between the two groups. Muscle thickness will also be measure at two separate time points during a follow up study at week 40 and 72 weeks from week 0.
Vastus lateralis and Bicep Brachi muscle thickness will be measured in the longitudinal and crosssectional plane via a 7.7-Hz linear transducer, using B-mode ultrasonography (Vscan Air; GE Healthcare, Chalfont St Giles, UK). Three images will be acquired at each site and analyzed using ImageJ v1.53t (National Institutes of Health, Bethesda, MD) software after being scaled from pixels to cm.
Isokinetic dynamometry (Bicep and Quadriceps) Peak Torque (Nm/kg)
Time frame · Peak torque in Nm/kg will be compared between pre, mid and post (weeks 0, 10 and 20) in both groups and plotted against time. As well as during follow ups at weeks 40 and 72
Knee extension and elbow flexion peak torque (PT) will be measured by an isokinetic dynamometer (Biodex Medical Systems, Shirley, NY). Participants will be positioned according to the Biodex manual (Biodex Medical Systems 3) at the familiarization visit and all subsequent visits. Before the test participants will warm up for 5 mins at 60-90rpm on a stationary bike (Watt Bike Atom; Wattbike Ltd, Nottingham, UK) and perform three repetitions on the dynamometer at 30, 60 and 90% effort. Participants will then perform 2 x 5 repetitions of maximal isokinetic contractions separated by 90s rest, the highest value will be taken as PT. Verbal encouragement will l be provided by the researcher during each test.
Isokinetic Dynamometry (Quadriceps and Bicep) Fatigue Profile (%)
Time frame · Fatigue profile (%) will be compared between pre, mid and post (weeks 0, 10 and 20) in both groups and plotted against time. As well as during follow ups at weeks 40 and 72
Knee extension and elbow flexion fatigue profile will then be measured on the isokinetic dynamometer (Biodex Medical Systems, Shirley, NY) after 3 minutes rest. Participants will perform 30 maximal-effort concentric repetitions on their dominant limbs.
Physical Function 60 second sit-to-stand test
Time frame · Sit to stand scores will be compared between groups and pre, mid and post intervention (weeks 0, 10 and 20). The measured again at follow up visits in week 40 and 72.
One minute Sit to Stand test (1MSTST) participants will be asked to stand up and sit down as many times as possible in 60 seconds on to a conventional chair without arm rests. The number of completed repetitions in 60 seconds will be recorded.
Dynamic Balance, Y-balance Test
Time frame · Balance test scores will be compared between groups and at pre, mid and post intervention (weeks 0, 10 and 20). Then again at follow up visits at weeks 40 and 72.
Dynamic balance will be measured using the Y-balance test (LQ-YBT). Participants will be asked to move a reach indicator block as far as possible in the anterior (ANT), posteromedial (PM), and posterolateral (PL) directions with their non standing foot from the central block of the YBT Kit TM (Fysio Supplies B.V). Participant hands will stay on hips and the heel will remain flat. Distances will be measured to the nearest half centimetre.
Handgrip dynamometry
Time frame · Grip strength scores will be compared between groups and pre, mid and post intervention (weeks 0, 10 and 20). Then again at follow up visits at weeks 40 and 72
Hand grip strength will be measured on each hand alternatively using the handgrip dynamometer (Takei, JAPAN) standing with arms parallel to the trunk. Three maximal attempts will be performed on each arm.
Body Mass (kg)
Time frame · Body mass will be taken weekly and reported to the researchers by participants for weeks 0-20. It will then also be taken at the follow up visits at weeks 40 and 72.
Body mass will be reported weekly with scales provided for the participants remotely and will be measured via BIA scales in the NPRU lab on each visit.
Height (cm)
Time frame · The measure will be taken at the commencement of the study at week 0 during the baseline visit.
Height will be measured in centimetres at the baseline visit.
Body Composition
Time frame · Fat and lean mass will also be measure every 4 weeks and also be measure at two separate time points during a follow up study at week 40 and 72 weeks from week 0.
Fat Mass and Lean Mass will be measured via BIA in the NPRU lab.
Plasma Tirzepatide
Time frame · Blood samples will be taken at weeks 0,4,8,10,12,16 and 20.
Plasma Tirzepatide will be measure retrospectively via LCMS
Hba1c
Time frame · Blood samples will be taken at weeks 0,4,8,10,12,16 and 20 as well as the follow up visits at weeks 40 and 72
Whole blood Hba1c will be measured via venepuncture blood sample.
Estradiol-β17
Time frame · Serum estradiol-β17 will be measured at baseline (week 0)
Serum estradiol-β17 will be analysed from baseline blood samples.
Progesterone
Time frame · Serum progesterone will be measured at baseline (Week 0)
Serum progesterone will be analysed from baseline blood samples.
Gastrointestinal Symptom Rating Scale Questionnaire (GSRS)
Time frame · The GSRS will be completed remotely from week 0-20 to assess GI symptoms and act as a monitoring tool of participants
The GSRS will be completed remotely from week 0-20 to assess GI symptoms and act as a monitoring tool of participants. Each question is scored from 1-7 with 1 showing no discomfort at all and 7 showing very severe discomfort. The scores to the 15 questions provide an overall score between 15-105 as well as grouped scores for different categories which are: reflux, abdominal pain, indigestion, diarrhoea and constipation.
Values are shown as posted at ClinicalTrials.gov, with their units. PepBank has not converted, pooled or compared them.
No results are posted for this trial.
A trial that is still running, or that stopped early, may post results later.
Registry data comes from ClinicalTrials.gov. Study results come from studies, not from the registry. How PepBank works
Studies that cite this trial.
1 study on this page
Indexing hint: Randomized controlled trial · 2022
Jastreboff et al. 2022The New England journal of medicinecited by 2,802
PMID 35658024DOI 10.1056/nejmoa2206038PUB-35658024
1 study on this page
Indexing hint: Randomized controlled trial · 2025
Look et al. 2025Diabetes, obesity & metabolismcited by 107
PMID 39996356PMC11965027DOI 10.1111/dom.16275PUB-39996356
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