Lower-Extremity Strength and Power in Elite Hockey Players With and Without Patellar Tendinopathy

NCT07356596 | Completed

• 1 other identifier: 2025-01700-02
• Study Type: observational
• Target: 28
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to identify differences in lower-extremity strength and power between elite ice hockey players with and without patellar tendinopathy using unilateral and bilateral comparisons. It applies a structured, cross-sectional methodology that combines clinical screening, performance testing, and ultrasound imaging to characterize patellar tendon structure and lower-limb function in elite hockey players. Players are objectively classified into healthy, unilateral, or bilateral patellar tendinopathy groups based on standardized ultrasound criteria. Strength and power outcomes are assessed under controlled conditions and normalized to body mass to allow fair between-group comparisons. Isokinetic concentric strength is evaluated during a split squat performed on a robotic resistance device, while peak power output is measured using a six-second all-out cycling test on a calibrated ergometer.

Conditions

Patellar Tendinitis

Outcome Measures

Primary Outcomes (2)

• Isokinetic leg strength

  Isokinetic leg strength measured as the concentric peak force (Newton)

  Day 2

• Wattbike Peak 6 test

  A six-second "all-out" peak power test on the Wattbike measured in Watt

  Day 3

Study Arms (3)

Unilateral PT

Ice-hockey players with unilateral patellar tendinopathy

Bilateral PT

Ice-hockey players with bilateral patellar tendinopathy

Control

Ice-hockey players without patellar tendinopathy

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: male
• Healthy Volunteers: No
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

Twenty-eight male players from the Swedish Hockey League (age: 25 ± 4.6 years; body mass index: 25.5 ± 2.0) participate in this study. Based on ultrasound findings, players are classified as healthy (HG; n = 8), unilateral patellar tendinopathy (UPTG; n = 8), or bilateral patellar tendinopathy (BPTG; n = 12). Of 35 consenting players, only those without current or prior knee injuries affecting lower-extremity function are included. A licensed physiotherapist conducts screening, excluding five players, while two additional players are excluded due to training-related injuries.

You may qualify if:

• Male
• Elite ice-hockey player
• ≥ 18 year

You may not qualify if:

• injuries to lower extremity that could influence test perfomance
• deviant passive and active range of motion in the knee joint
• pain in the knee during squatting, lunging, or jumping
• limping while walking
• positive patellar The Royal London Hospital Test
• palpable or visible the knee joint effusion
• positive Lachmann, varus/valgus stress test, patellar apprehension, or Murray's/Apley's test
• hypo- or atrophic quadriceps on only one side (side difference with limb symmetry index \< 90%).

Sponsors & Collaborators

• Linnaeus University: lead

Study Sites (1)

Sofia Ryman Augustsson

Kalmar, 391 82, Sweden

Location

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: December 23, 2025
• First Posted: January 21, 2026
• Study Start: January 1, 2025
• Primary Completion: March 1, 2025
• Study Completion: December 23, 2025
• Last Updated: January 21, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

SE (1)