A Study of the Effect of Time-of-day of Training on Chronic Patellar Tendinopathy

Tendinopathy: Optimal Time for Management Through Exercise (TENDOTIME) - a Randomised Controlled Study Comparing Targeted Training Performed Morning and Late Afternoon in a 12-week Intervention Program on Chronic Patellar Tendinopathy

The study is a 12-week human study where 60 participants with chronic patellar tendinopathy (more than 3 months symptoms duration) are randomised to undergo 12 weeks of targeted resistance exercise either in the morning or in the late afternoon. The overall aim is to investigate when the best time of the day to perform muscular strength training therapy towards tendinopathy is. The study will also include 10 healthy controls who will not perform any exercise training.

Inclusion Criteria:

• Sports active men and women
• Age (18-55) years old
• BMI (18.5-30)
• Uni- or bilateral patellar tendinopathy
• Symptom onset >90 days ago

Exclusion Criteria:

• Patellar tendinopathy longer than 24 months
• Previous surgery in the knee on the ipsilateral side
• Corticosteroid injection in the patellar tendon on the ipsilateral side within the last 6 months
• Any confounding diagnosis to the knee joint
• Known arthritis
• Known diabetes
• Known rheumatic disorders
• Inability to follow rehabilitation or complete follow-ups
• Enrolled in a resistance based-rehabilitation program for the affected patellar tendon within the previous 3 months
• Have an occupation where it is not feasible to avoid pain provoking tasks
• Pregnancy
• Have sleeping disorders or disruptions, e.g., night shift work
• Use of medicines or supplements known to affect collagen synthesis or sleep