Eccentric Training Effects on Hamstrings Structure, Strength, and Sprint Performance

NCT05455346 | Completed

• 3 other identifiers: 2022-0763Protocol Version 2/27/2023A176000
• Study Type: interventional
• Target: 32
• Locations: 1 country
• Sites: 1

Brief Summary

The overall goal of this study is to investigate the effects of a 6-week training program between two hamstring exercises-the Romanian deadlift (RDL) and the Nordic hamstring exercise (NHE)-on hamstring strain injury risk factors and sprint performance.

Conditions

Exercise Training; Sport; Running; Ultrasound Imaging; Elastography; Healthy

Outcome Measures

Primary Outcomes (3)

• Biceps femoris long head fascicle length

  Baseline

• Biceps femoris long head fascicle length

  Post-intervention (6 weeks)

• Biceps femoris long head fascicle length

  Post 2 week de-training (8 weeks)

Secondary Outcomes (6)

• Biceps femoris long head pennation angle

  Baseline, Post-intervention (6 weeks), Post 2 week de-training (8 weeks)

• Biceps femoris long head muscle thickness

  Baseline, Post-intervention (6 weeks), Post 2 week de-training (8 weeks)

• Biceps femoris long head anatomical cross sectional area

  Baseline, Post-intervention (6 weeks), Post 2 week de-training (8 weeks)

• Romanian deadlift (RDL) 3-repetition maximal strength

  Baseline, Post-intervention (6 weeks), Post 2 week de-training (8 weeks)

• Nordic hamstring exercise (NHE) maximal strength

  Baseline, Post-intervention (6 weeks), Post 2 week de-training (8 weeks)

Other Outcomes (2)

• Biceps femoris long head regional shear wave speed

  Baseline, Post-intervention (6 weeks), Post 2 week de-training (8 weeks)

• Inertial measurement unit (IMU)-derived trunk, hip, knee, and ankle kinematics

  Baseline, Post-intervention (6 weeks), Post 2 week de-training (8 weeks)

Study Arms (2)

Romanian Deadlift

EXPERIMENTAL

The training intervention groups will undergo the same program with the only difference being the interventional hamstring exercise. The program will consist of a 2-week acclimatization period followed by 4-weeks of progressive training. The RDL will be performed with a 6 second eccentric component with the athlete returning to the start position with a maximal concentric hip extension.

Diagnostic Test: Ultrasound imaging; Other: Hamstring Eccentric Strength Testing; Other: Maximal 60 m Sprint; Other: Romanian Deadlift

Nordic Hamstring Exercise

ACTIVE COMPARATOR

The training intervention groups will undergo the same program with the only difference being the interventional hamstring exercise. The program will consist of a 2-week acclimatization period followed by 4-weeks of progressive training. During the acclimatization period, the relative intensity will be lower compared to the 4-week progressive training to ensure each participant performs the exercise with proper technique. During the subsequent progressive training weeks, the participants will perform the NHE without the bands.

Diagnostic Test: Ultrasound imaging; Other: Hamstring Eccentric Strength Testing; Other: Maximal 60 m Sprint; Other: Nordic hamstring exercise

Interventions

Ultrasound imaging DIAGNOSTIC_TEST

Ultrasound B-mode images will be unilaterally collected from the biceps femoris muscle of the dominant limb for each participant using a commercial ultrasound system and linear array transducer. Standardized image locations will correspond to 33%, 50%, and 67% of the thigh length from the ischial tuberosity. Three repeat longitudinal extended-field-of-view images of the entire biceps femoris muscle will be collected for offline analysis for fascicle length, muscle thickness, and pennation angle. Transverse extended-field-of-view images will be captured at the proximal, mid-belly, and distal locations to determine regional anatomical cross-sectional area of the biceps femoris long head muscle. To determine changes in tissue stiffness via ultrasound shear wave speed, the same transducer will be placed in the same locations in a longitudinal view. Shear wave maps will be generated by the ultrasound system and shear wave speed measures extracted from the middle of the map.

Nordic Hamstring Exercise; Romanian Deadlift

Hamstring Eccentric Strength Testing OTHER

Prior to each test, participants will perform a standardized 5-minute general warm-up followed by a task-specific warm-up including 3 sets of submaximal trials. Load increases (5-20%) will be added for each RDL 3-repetition maximum trial attempt until the participant cannot complete 3 repetitions through the full range of motion using proper technique. A 3-minute rest will be administered between all warm-up and testing sets to allow for full recovery. Participants will kneel on a commercial device used to assess maximum eccentric knee flexor strength via uniaxial load cells with their ankles secured into fixed hooks. Participants will slowly lower their torso to the ground with arms crossed across their chest and without bending at the hips or spine. The maximal test will consist of 1 set of 3 maximal repetitions. If participants can control lower themselves to the ground, then they will hold barbell plates (5-10 lb increments) across their chest while performing the NHE.

Nordic Hamstring Exercise; Romanian Deadlift

Maximal 60 m Sprint OTHER

Following a standardized warm-up, inertial measurement units (IMUs) will be placed on the sternum, sacrum, and bilaterally on the thighs, legs, and foot. Each participant will perform a total of 3 maximal 60 m sprints from a standing position with 1.5-3 min rest in between each trial to minimize the effects of fatigue.

Nordic Hamstring Exercise; Romanian Deadlift

Romanian Deadlift OTHER

The RDL intervention will be performed twice per week for 6 weeks. Participants will hinge at the hips lowering the bar to just below their patella before reversing the movement. The RDL will be performed with a 6 second eccentric component and returning to the start position with a maximal concentric hip extension.

Also known as: RDL

Romanian Deadlift

Nordic hamstring exercise OTHER

The NHE will be performed twice per week for 6 weeks. Participants will be instructed to maintain their ankles in a dorsiflexed position, lower themselves as close to the ground as possible at a constant and controlled speed while maintaining a neutral position of the hips and trunk, and to cross their arms in front of their chest.

Also known as: NHE

Nordic Hamstring Exercise

Eligibility Criteria

• Age: 18 Years - 25 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• years of age
• Have \>6 months experience in resistance training

You may not qualify if:

• History of hamstring strain injury within the last 12 months
• History of lower extremity surgery
• Current musculoskeletal injury to the lower extremity
• Females who are currently pregnant
• Individuals who indicate they are unwilling to refrain from novel outside training activities
• Individuals who do not complete 75% (9 out of 12) of the training sessions

Sponsors & Collaborators

• University of Wisconsin, Madison: lead

Study Sites (1)

University of Wisconsin

Madison, Wisconsin, 53705, United States

Location

Related Publications (2)

• Crawford SK, Sandberg C, Vlisides J, Thompson Q, Mosiman SJ, Heiderscheit BC, Hickey JT. Hamstrings Muscle Architecture and Morphology Following 6 wk of an Eccentrically Biased Romanian Deadlift or Nordic Hamstring Exercise Intervention. Med Sci Sports Exerc. 2025 Aug 1;57(8):1799-1809. doi: 10.1249/MSS.0000000000003701. Epub 2025 May 14.

  PMID: 40085810 DERIVED

• Crawford SK, Hickey J, Vlisides J, Chambers JS, Mosiman SJ, Heiderscheit BC. The effects of hip- vs. knee-dominant hamstring exercise on biceps femoris morphology, strength, and sprint performance: a randomized intervention trial protocol. BMC Sports Sci Med Rehabil. 2023 Jun 26;15(1):72. doi: 10.1186/s13102-023-00680-w.

  PMID: 37365624 DERIVED

MeSH Terms

Interventions

Ultrasonography

Intervention Hierarchy (Ancestors)

Diagnostic Imaging; Diagnostic Techniques and Procedures; Diagnosis

Study Officials

• Scott K Crawford, PhD

  University of Wisconsin, Madison

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Each eligible participant will be block randomized (1:1 allocation) to either the RDL or the NHE intervention group

Study Record Dates

• First Submitted: July 7, 2022
• First Posted: July 13, 2022
• Study Start: December 2, 2022
• Primary Completion: December 8, 2023
• Study Completion: December 8, 2023
• Last Updated: December 21, 2023

Record last verified: 2023-12

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)