An interventional study of Progressive resistance exercise with an emphasis on eccentric hamstring loading. in Hypermobile EDS (hEDS), Hypermobile Ehlers-Danlos Syndrome and Hypermobile Spectrum Disorder, sponsored by University of Calgary. Not yet recruiting at 1 site in Canada. Open to female participants aged 18 Years to 55 Years. Per ClinicalTrials.gov, last updated 2026-06-04.
Sponsored by University of Calgary · Not applicable, Interventional, and Basic science
The goal of this clinical trial is to determine how strengthening the hamstring muscles affects the knee joint in people living with hypermobility spectrum disorders (HSD) and hypermobile Ehlers-Danlos syndrome (hEDS). The main questions it aims to answer are:
Participants will:
Hypermobility spectrum disorders (HSD) and hypermobile Ehlers-Danlos syndrome (hEDS) affect 1 in 500 people, predominantly females. While exercise is known to be beneficial for HSD/hEDS, the effect of eccentric exercise on passive joint stability, the functional capacity to perform daily activities, and quality of life remains unknown. This clinical trial aims to determine the effects of a 12-week eccentric hamstring strengthening intervention for females with HSD/hEDS on knee joint laxity, performance during walking and stair climbing, and quality of life. This study will have important implications for understanding the impacts of exercise in HSD/hEDS. This can then inform clinical guidance and recommendations around lower limb exercise for this population.
28 studies on the registry are indexed under Ehlers-Danlos syndrome type 3; 9 are open to participants now.
This study's planned enrollment of 20 is below the median of 32 across 16 interventional studies indexed under Ehlers-Danlos syndrome type 3.
Browse Ehlers-Danlos syndrome type 3 studies →University of Calgary is the lead sponsor of 703 studies on the registry; 196 are open to participants now.
Of its 10 completed or terminated interventional studies of FDA-regulated products, 2 (20%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
All participants will complete a 12-week supervised lower limb strengthening program focused on eccentric hamstring loading. Participants will complete two training sessions per week with at least 48 hours between training sessions. Multiple classes will be offered each week to increase participation opportunity, with morning classes (8-9am) and evening classes (6-7pm) being offered on Mondays and Thursdays. Each class will be led by the same trained kinesiologist and cover the same training protocol within a given week, regardless of the day or time.
Behavioral: Progressive resistance exercise with an emphasis on eccentric hamstring loading.
The exercise intervention consists of a 12-week supervised lower limb strengthening program focused on eccentric hamstring loading. This program is adapted from a lower limb progressive resistance training protocol that was well-tolerated and effective in people with HSD/hEDS. Each exercise session will start with a 10-minute aerobic warm up. This will be followed by the lower limb strengthening exercises, and a 5-minute aerobic cooldown. The lower limb exercises will include forward lunges and seated machine weights (leg press, leg extension, leg curl, calf raise). At weeks 6-11, eccentric hamstring loading will be initiated by utilizing the 2:1 technique of two limbs performing concentric action at once and then a single limb performing the eccentric action in a seated leg curl machine. This is an established eccentric loading protocol for the hamstring muscle group.
Also known as: Exercise, Progressive Resistance Training, Eccentric Exercise
Knee Joint Laxity
Anterior knee joint laxity measured in millimeters using a KT-2000 Knee Ligament Arthrometer at 67N, 89N, and 133N of applied force, as well as maximum displacement. Posterior knee joint laxity will be assessed at 67N of applied force. Changes in knee joint laxity at each level of applied force will be assessed from baseline to 4, 8, 12, 18, and 24 weeks after baseline.
Time frame: Measured at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
Knee Joint Stiffness
Anterior knee joint stiffness calculated from the change in displacement divided by the change in force from 0N to 67N, 67N to 89N, and 89N to 133N. Posterior knee joint stiffness will be calculated between 0N and 67N of force. Changes in stiffness will be assessed from baseline to 4, 8, 12, 18, and 24 weeks after baseline.
Time frame: Measured at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
Isokinetic eccentric knee flexion strength
Isokinetic eccentric knee flexion strength at 60 degrees per second will be measured using a Biodex Dynamometer. Change in eccentric knee flexion strength will be assessed from baseline to 4, 8, 12, 18, and 24 weeks after baseline.
Time frame: Measured at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
Isokinetic concentric knee flexion strength
Isokinetic concentric knee flexion strength at 60 degrees per second will be measured using a Biodex dynamometer. Change in concentric knee flexion strength will be assessed from baseline to 4, 8, 12, 18, and 24 weeks after baseline.
Time frame: Measured at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
Hamstrings:Quadriceps Co-Activation
Co-activation between the hamstrings and quadriceps muscles will be measured using Delsys surface electromyography sensors during dynamometry, the 6-Minute Walk Test, and the stair climb test. Changes in hamstring:quadriceps co-activation will be assessed from baseline to 4, 8, 12, 18, and 24 weeks after baseline.
Time frame: Measured at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
6-Minute Walk Test
Functional capacity/performance will be assessed using the 6-Minute Walk Test, which measures the distance in meters that a participant can walk in 6 minutes. Changes in performance will be assessed from baseline to 4, 8, 12, 18, and 24 weeks after baseline.
Time frame: Measured at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
Pain Severity Score
Pain severity score (from 0 to 40) will be calculated from the pain severity components of the Brief Pain Inventory. The Brief Pain Inventory is a questionnaire that measures the location of pain (body diagram), pain severity (4 questions with numeric rating scales from 0-10, 0 indicating "no pain" and 10 indicating "pain as bad as you can imagine"), medications or treatments, a numeric rating scale (0-100%, 0% indicating "no relief" and 100% indicating "complete relief") for relief of pain from medications or treatments, as well as pain interference (7 questions with numeric rating scales from 0-10, 0 indicating "does not interfere" and 10 indicating "completely interferes"). Changes in pain severity score will be assessed from baseline to 4, 8, 12, 18, and 24 weeks after baseline.
Time frame: Measured at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
Safety of the Intervention
Safety of the intervention will be monitored and determined by the number of adverse events reported by participants to either the exercise kinesiologist during the exercise sessions, or to the research team during data collection or via email.
Time frame: Monitored throughout the study from baseline to 24 weeks.
Tolerability of the Intervention
Tolerability of the exercise intervention will be assessed using the following metrics: Number of participants that withdraw from the study (along with reasons for withdrawal), number of exercises classes completed after 12 weeks, and pain severity (100mm visual analog scale) before and after each exercise class.
Time frame: Monitored throughout the study, from baseline to week 24.
Acceptability of the Intervention
Participants will be asked open ended questions via an online survey at 12, 18 and 24 weeks after baseline asking about how acceptable they found the exercise program to be.
Time frame: Measured at the follow up visits for week 12, 18, and 24.
Adherence and Maintenance of Exercises
Adherence to the exercise program and maintenance of the exercises following completion of the 12 weeks of supervised classes will be assessed using open ended questions via an online survey send to participants at 12, 18, and 24 weeks after baseline.
Time frame: Measured at follow up visits for week 12, 18, and 24.
Knee Joint Range of Motion
Knee joint range of motion will be measured in degrees both actively and passively using a goniometer. Changes in range of motion will be assessed from baseline, 4, 8 , 12, 18, and 24 weeks.
Time frame: Measured at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
Isometric knee flexion and extension strength
Isometric knee flexion and extension strength will be measured using dynamometry at 90 degrees of knee flexion. Changes in isometric flexion and extension strength will be assessed from baseline to 4, 8, 12, 18, and 24 weeks after baseline.
Time frame: Measured at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
Stair Climb Test
Functional capacity/performance will also be assessed using a Stair Climb Test, which measures the time that a participant can ascend and descent a set of stairs. Changes in performance will be assessed from baseline to 4, 8, 12, 18, and 24 weeks after baseline.
Time frame: Measured at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
Pain Interference Score
Pain interference score (from 0 to 70) will be calculated from the pain severity components of the Brief Pain Inventory. The Brief Pain Inventory is a questionnaire that measures the location of pain (body diagram), pain severity (4 questions with numeric rating scales from 0-10, 0 indicating "no pain" and 10 indicating "pain as bad as you can imagine"), medications or treatments, a numeric rating scale (0-100%, 0% indicating "no relief" and 100% indicating "complete relief") for relief of pain from medications or treatments, as well as pain interference (7 questions with numeric rating scales from 0-10, 0 indicating "does not interfere" and 10 indicating "completely interferes").Changes in pain interference score will be assessed from baseline to 4, 8, 12, 18, and 24 weeks after baseline.
Time frame: Measured at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
Knee Pain
Knee pain will be determined before and after each exercise session using a 100mm visual analog scale (VAS), with 0 indicating "no pain" and 100 indicating "pain as bad as you can imagine". Knee pain will also be determined at baseline and each follow up assessment using a 100mm VAS for the average knee pain over the last 7 days during rest and during walking, with 0 indicating "no pain" and 100 indicating "pain as bad as you can imagine".
Time frame: Measured before and after each exercise class, and at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
Kinesiophobia
Fear related to physical activity will be measured using the Tampa Scale for Kinesiophobia at baseline and each follow up assessment. The Tampa Scale is scored from 17 questions related to pain, injury, physical activity, and fear. The answers for each question are structured as a 4 point Likert scale (1 - "strongly disagree", 2 - "disagree", 3 - "agree", or 4 - "strongly agree").
Time frame: Measured at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
Fatigue
Generalized fatigue will be measured using the Fatigue Severity Scale (FSS) at baseline and each follow up assessment. The FSS contains 9 questions relating to fatigue on a 7 point Likert scale. A 100mm visual analog scale will also accompany the FSS asking to "indicate on the line the point that best describes your fatigue during the past week", with 0 indicating "very alert" and 100 indicating "extremely fatigued". Additionally, a 100mm visual analog scale for fatigue will be measured before and after each exercise class with with 0 indicating "very alert" and 100 indicating "extremely fatigued".
Time frame: Measured before and after each exercise class, and at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
Physical Activity Level
Physical activity levels over the past 7 days will be quantified at baseline and at each follow up assessment using the International Physical Activity Questionnaire (IPAQ). The IPAQ looks at the duration of time spent doing moderate or vigorous activities across job-related physical activity, transportation physical activity, housework/house maintenance/caring for family and recreation/sport/leisure time physical activity.
Time frame: Measured at all 6 outcome assessments (baseline, 4, 8, 12, 18, and 24 weeks).
Impact of Hypermobility
The impacts of hypermobility on quality of life and physical function will be assessed using the Bristol Impact of Hypermobility (BiOH) questionnaire. The BiOH is scored from 0 to 360, with higher scores indicating greater severity.
Time frame: Measured at baseline and each follow up assessment at 4, 8, 12, 18, and 24 weeks.
Quality of Life
Quality of life will also be measured using the RAND 36-item short form (SF-36). The SF-36 contains 36 multiple choice questions that are reported as 8 domains, including physical functioning, role limitations due to physical health, role limitations due to emotional problems, energy/fatigue, emotional well-being, social functioning, pain, and general health.
Time frame: Measured at baseline and each follow up assessment at 4, 8, 12, 18, and 24 weeks.
Knee Injury and Osteoarthritis Outcome Score
The Knee Injury and Osteoarthritis Outcome Score (KOOS) is a questionnaire which measures quality of life and functional outcomes within domains of pain, symptoms, activities of daily living, sport/recreation, and knee-related quality of life. Each domain includes questions with 5-point Likert scales, including how often is your knee painful (never, monthly, weekly, daily, always), symptom severity (none, mild, moderate, severe, extreme), symptom presentations (never, rarely, sometimes, often, always), difficulty with activities (none, mild, moderate, severe, extreme), lifestyle modifications (not at all, mildly, moderately, severely, totally), and concerns (not at all, mildly, moderately, severely, extremely).
Time frame: Measured at baseline and at each follow up assessment at 4, 8, 12, 18, and 24 weeks.
Knee Joint Proprioception
Knee joint proprioception will be measured with a joint angle reproduction test using isokinetic dynamometer. The participant will be moved to a particular knee angle, then asked to reproduce this knee angle. The error in degrees between the original joint angle and the participant's reproduced joint angle will be calculated.
Time frame: Measured at baseline and at each follow up assessment at 4, 8, 12, 18, and 24 weeks.
Work Status
Work Status will be reported at baseline and each follow up assessment as a multiple choice question with the following answers: not working by choice, part-time student, full-time student, retired, working full-time, working part-time, on temporary medical leave or short-term disability, on long-term disability (private, Canada Pension Plan Disability, or Workers' Compensation Board-Alberta income supplementation), other (please specify).
Time frame: Measured at baseline and each follow up assessment at 4, 8, 12, 18 and 24 weeks.
Plan to share: Undecided
No publications or documents are linked to this record.
Start is estimated for Jun 2026; primary completion for May 2027, 11 months later.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in May 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Ehlers-Danlos syndrome type 3 →