←back to Blog

Impact of a Targeted 8-Week Exercise Program on Pain Measures and Isokinetic Muscle Strength in Females With Patellofemoral Pain Syndrome: A Randomized Controlled Trial

Physiother Res Int. 2025 Oct;30(4):e70093. doi: 10.1002/pri.70093.

ABSTRACT

BACKGROUND AND PURPOSES: Patellofemoral pain syndrome (PFPS) is a prevalent condition among physically active females and is often associated with reduced hip and knee muscle strength, altered biomechanics, and pain-related disability. Weight-bearing exercise programs may enhance neuromuscular control and functional outcomes, but their effects on multiple objective and subjective measures have not been comprehensively studied in this population. Therefore, the main purpose of this study was to investigate the effect of the weight-bearing exercise for better balance (WEBB) program on isokinetic hip and knee muscle strength, pain intensity, pain sensitivity, and disability in females with PFPS.

METHODS: A randomized controlled trial (RCT) was conducted on 30 females with clinically diagnosed PFPS. Participants were randomly allocated to either an experimental group (n = 15), receiving 8 weeks of a supervised WEBB program, or a control group (n = 15), did not receive any intervention. Outcomes included nine dependent variables: isokinetic peak torque of hip and knee muscles (flexors, extensors, abductors, adductors, knee flexors, knee extensors) measured by Biodex Isokinetic Dynamometer, pain intensity evaluated by Visual Analogue Scale (VAS), pressure pain threshold (PPT) measured by digital algometer, and disability assessed by Oswestry Disability Index (ODI). Measurements were taken at baseline and after 8 weeks of the WEBB program.

RESULTS: Within the experimental group, significant improvements were observed after performing the WEBB program across all nine measured outcomes (p < 0.05), including increases in isokinetic strength, reductions in pain intensity, elevated PPT values, and decreased ODI scores. Between-group comparisons revealed statistically significant improvements in several variables favoring the experimental group post intervention. Specifically, there were statistically significant increases in isokinetic strength of hip flexors, hip adductors, knee flexors, and knee extensors in addition to a significant reduction in pain intensity and functional disability (p < 0.05). However, the other variables including isokinetic strength of hip extensors, hip abductors and ODI scores did not show any statistically significant differences between groups (p > 0.05).

DISCUSSION: The introduced WEBB program demonstrated significant within-group improvements in all measures of muscular strength, pain, and disability in females with PFPS. While between-group differences were evident in some outcomes, further studies are warranted to explore the long-term and differential effects on specific muscle groups and functional indices.

TRIAL REGISTRATION: The study was registered at https://clinicaltrials.gov/.

PMID:40719231 | DOI:10.1002/pri.70093