Efficacy Of Montmorency Tart Cherry Juice For The Treatment Of Patellofemoral Pain In Recreational Athletes

Abstract

PURPOSE: The aim of this study was to test the ability of Montmorency Tart Cherry Juice (MTCJ) to provide symptom relief in recreational athletes with patellofemoral pain (PFP) and to understand the biological mechanisms for any change.

METHODS: Twenty-four participants suffering from mild to moderate PFP were randomised in to one of two groups. The participants consumed 60 ml daily (2 x 30 ml) of MTCJ or a placebo (PL) for 6 weeks. Outcome variables were measured at baseline and immediately after 6 weeks of supplementation in both groups. Questionnaire outcome variables included: self-reported pain (KOOS-PF), mood-states and psychological wellbeing (COOP-WONCA chart) and finally sleep quality (Pittsburgh Sleep Quality Index [PSQI]). Venous blood was taken and analysed for plasma urate, human creatinine, Human TNF-α, total antioxidant capacity and high sensitivity C-reactive protein (CRP). Questionnaire data were examined using 2 (group - PL & MTCJ) x 2 (time - pre & post) mixed ANCOVA’s, with the pre scores serving as covariates for the PSQI and COOP-WONCA analyses, and the pre scores and experimental anthocyanins acting as covariates for the KOOS-PF. Blood biomarkers were examined using 2 (group - PL & MTCJ) x 2 (time - pre & post) mixed ANOVA’s.

RESULTS: There was a group × time interaction for KOOS-PF scores, with the PL group having a significant improvement (Pre: 63.3 ± 18.1 & Post: 78.7 ± 16.1) in KOOS-PF scores (P < 0.05, pη2 = 0.55) but no change in MTCJ (Pre: 62.0 ± 16.5 & Post: 60.0 ± 20.6; P ≥ 0.05, pη2 = 0.01). There were no significant differences (P ≥ 0.05) in COOP WONCA (PL: [Pre: 1.8 ± 0.5 & Post: 2.1 ± 0.4], MTCJ: [Pre =1.9 ± 0.5 & Post =2.3 ± 0.7]) or PSQI scores (PL: [Pre: 4.6 ± 3.0 & Post: 5.1 ± 3.0], MTCJ: [Pre: 5.8 ± 2.7 & Post: 6.4 ± 2.5]). There were no significant differences (P ≥ 0.05) between any of the blood biomarkers measured, as evident from CRP levels (PL: [Pre: 1751 ± 679 μg/ml & Post: 1643 ± 626 μg/ml] and MTCJ: [Pre: 2330 ± 914 & Post: 1906 ± 1113 μg/ml]).

CONCLUSIONS: MTCJ supplementation for recreational athletes with PFP does not appear to: 1) be an effective treatment for PFP symptoms; 2) have any effect on psychological wellbeing as measured by the COOP WONCA; 3) improve sleep quality; or 4) have any effect on inflammatory biomarkers.