The aim of the present investigation is to evaluate the efficacy of Mangoselect®, a mangosteen extract, and of a formulation containing Mangoselect®, in subjects suffering from activity/exercise-induced knee joint pain/discomfort, during a 12-week supplementation period. Subjective discomfort improvement will be assessed with both WOMAC questionnaire and pain Visual Analogic Scale (VAS); functional joints features, quality of life, and inflammatory markers, will also be assessed. Finally, long lasting benefits will additionally be evaluated 4 weeks after the end of the supplementation period. The design of the study is double-blind, randomized, multi-arm, parallel and placebo controlled.

Inclusion Criteria:

• Physically active volunteers
• BMI 22-29.9 kg/m2
• Declaring knee joint pain during and/or after activity/exercise
• Joint knee pain rated of at least 4 cm on a 10 cm VAS following activity/exercise
• Diagnosed osteoarthritis grade I or II according to Kellgren-Lawrence classification

Exclusion Criteria:

• Diagnosed inflammatory joint disorder or osteoarthritis grade III or more according to Kellgren-Lawrence classification
• Currentlu chronically taking pain killer drugs or dietary supplement or intra-articular treatment 3 months before selection
• Anemia
• Subjects with knee/joint surgery/replacement in the past 10 years
• Significant injury of the studied knee joint 12 months before selection
• Unable to carry out functional tests and/or questionnaires
• Currently participating or having participated in another clinical trial in the 3 previous months
• Pregnant women and women positive at Beta-HCG serology test
• Any condition that the investigator believes would interfere with the ability to provide inform consent, or comply with study instructions, or confound the interpretations of the study results, or put the volunteer at undue risk
• Allergy to one of the component of the supplements