Eccentric decline squat protocol offers superior results at 12 months compared with traditional eccentric protocol for patellar tendinopathy in volleyball players. (2005)

Abstract
BACKGROUND:

Conservative treatment of patellar tendinopathy has been minimally investigated. Effective validated treatment protocols are required.
OBJECTIVES:

To investigate the immediate (12 weeks) and long term (12 months) efficacy of two eccentric exercise programmes for the treatment of patellar tendinopathy.
METHODS:

This was a prospective randomised controlled trial of 17 elite volleyball players with clinically diagnosed and imaging confirmed patellar tendinopathy. Participants were randomly assigned to one of two treatment groups: a decline group and a step group. The decline group were required to perform single leg squats on a 25 degrees decline board, exercising into tendon pain and progressing their exercises with load. The step group performed single leg squats on a 10 cm step, exercising without tendon pain and progressing their exercises with speed then load. All participants completed a 12 week intervention programme during their preseason. Outcome measures used were the Victorian Institute of Sport Assessment (VISA) score for knee function and 100 mm visual analogue scale (VAS) for tendon pain with activity. Measures were taken throughout the intervention period and at 12 months.
RESULTS:

Both groups had improved significantly from baseline at 12 weeks and 12 months. Analysis of the likelihood of a 20 point improvement in VISA score at 12 months revealed a greater likelihood of clinical improvements in the decline group than the step group. VAS scores at 12 months did not differ between the groups.
CONCLUSIONS:

Both exercise protocols improved pain and sporting function in volleyball players over 12 months. This study indicates that the decline squat protocol offers greater clinical gains during a rehabilitation programme for patellar tendinopathy in athletes who continue to train and play with pain.

Diagnosis:  Patellar Tendinopathy

Outcome:  VISA-P and VAS scores comparing eccentric single leg squat stepping down a block, vs. single leg squat on a 25 degree decline board to increase quadriceps recruitment. Scores on graph so approximate but step group VISA-P was 56 at baseline, 66 at 12 weeks and 68 at 12 months. Decline group was 62 at baseline, 78 at 12 weeks, and 84 at 12 months. VAS score improved over time in both groups but was not significantly different.

When Assessed:  12 weeks and 12 months.

Subjects:  17 elite volleyball players 18-35 years old

Protocol:  3 sets of 15 reps of eccentric single leg squats performed twice per day in both groups starting with body weight. The step group (10 cm height) was instructed to train with “minimal pain” while the decline (25 degree) group were instructed to train into “moderate” pain. The decline group increased resistance when pain decreased, while the step group was instructed to progress speed from slow to fast before increasing resistance as per Stanish protocol.

Other Activity:  Sounds like exercise protocol was initiated and completed in the preseason and then the athletes were tracked for the full competitive season with no additional intervention.

My Comments:  Interesting for several reasons. First it is impossible to say if decline board is better than the step down because the exercise protocol was different (more pain allowed in decline group, increasing speed in step down group). I think perhaps a leg extension machine might be best still as you know for sure you are getting 100% quadriceps involvement as both above interventions allow for at least some degree of substitution from other muscles. Both groups improved but not as well as Achilles tendinopathy studies, that Alfredson was also a part of. Noted that most competitive athletes training with pain and patellar tendinopathy have a VISA-P of 50-80 which perhaps indicates that if you are below 50 it might be wise to take a break from sports.