Effects of Resistance Training on Patellar Tendon Properties in People With Patellar Tendinoapthy

Condition(s) studied

Investigational drug(s) / intervention(s)

Eccentric Training: The intervention consists of 12 weeks of resistance training, with a frequency of three times per week. Participants in this group will perform two exercises on a leg press and knee extension machine at their own training facility. This intervention has a repetition time of four seconds, with only the eccentric phase of the movement being performed. They will rest between two and three minutes between sets and will perform the exercises as long as their pain level is less than or equal to four on a pain scale from 0-10. The training parameters are the following, applying to both leg press and knee extension exercises: Week 1: 3 sets of 15 repetitions at 60% of their 1-repetition maximum (1RM) Week 2 and 3: 3 sets of 12 repetitions at 70% of their 1RM Week 4 and 5: 3 sets of 10 repetitions at 75% of their 1RM Week 6 to 12: 4 sets of 8 repetitions at 80% of their 1RM.

Heavy-Slow Resistance Training: The intervention consists of 12 weeks of resistance training, with a frequency of three times per week. Participants in this group will perform two exercises on a leg press and knee extension machine at their own training facility. This intervention has a repetition time of four seconds, of which two seconds will be spent on the concentric phase and two seconds on the eccentric phase of the movement being performed. They will rest between two and three minutes between sets and will perform the exercises as long as their pain level is less than or equal to four on a pain scale from 0-10. The training parameters are the following, applying to both leg press and knee extension exercises: Week 1: 3 sets of 15 repetitions at 60% of their 1-repetition maximum (1RM) Week 2 and 3: 3 sets of 12 repetitions at 70% of their 1RM Week 4 and 5: 3 sets of 10 repetitions at 75% of their 1RM Week 6 to 12: 4 sets of 8 repetitions at 80% of their 1RM.

Study summary

This study aims to investigate the effects of two different resistance training interventions on the structural, morphological, mechanical, and functional properties of the thigh muscles (in particular the quadriceps femoris) and the patellar tendon, in participants with current patellar tendinopathy.

Eligibility

Primary outcome measure(s)

• Tendon Thickness — From enrollment to the end of training at 12 weeks
  Anteroposterior thickness of the patellar tendon (in milimiters) measures by B-Mode Ultrasound (Aixplorer V12.3 Supersonic Imaging, France) with a SuperLinear 15-4 MHz probe. Three images at the same position will be taken for further analysis with the software ImageJ.
• Tendon sitffness — From enrollment to the end of training at 12 weeks
  Stiffness of the patellar tendon (in kilopascal) will be measured with Shear-Wave Elastrography (Aixplorer V12.3, Supersonic Imaging, France). The measurement site is 0.5cm from the patellar apex, and five videos of 15 seconds will be recorded for further analysis with Matlab.
• Tendon CSA — From enrollment to the end of training at 12 weeks
  Cross-sectional area of the patellar tendon (in centimiters) on its proximal, middle and distal part, will be measured with B-Mode Ultrasound (Aixplorer V12.3, Supersonic Imaging, France). Three images per site, accounting for a total of 9 images, will be taken for further analysis with the software ImageJ.
• Fascicle length — From enrollment to the end of training at 12 weeks
  Length of the fascicles of the vastus lateralis muscle (in centimiters) will be measures with Extended Field of View (Panoramic) B-Mode Ultrasound (Aixplorer V12.3, Supersonic Imaging, France). Five images will be taken for further analysis with the software ImageJ.
• Muscle Strength — From enrollment to the end of training at 12 weeks
  Maximum voluntary isometric torque of the knee extensors (in newton per meters) will be measured with the Isomed2000, Germany device. Three trials will be performed, with three minutes of rest in between, and the trial with the maximum peak torque will be taken for analysis.
• 1 repetition maximum — From enrollment to the end of training at 12 weeks
  Maximum strength of the leg press and knee extension exercises (in kilograms) will be measured with the leg press and knee extension devices (compass540, Physiomed, Germany). Participants will perform repetitions with increasing weights, until they can perform a maximum of eight repetitions with a specific weight. This weight will be then used to estimate their maximum 1RM, to further calculate the training loads.
• Overall Pain — From enrollment to the end of training at 12 weeks
  Pain assessed at rest and during a single-leg-decline squat (SLDS) will be assessed with the numerical rating scale of 11 points called Visual Analogue Scale (VAS). Higher values mean higher pain levels.
• Functionality — From enrollment to the end of training at 12 weeks
  Functionality assessed with the VISA-P Questionnaire. This questionnaire includes 10 questions with a score from 0 to 10, for a maximum questionnaire score of 100 points. Higher scores mean better functionality.

Trial sites (1)

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