biostudies-literatureCoelho JMFundação para a Ciência e a TecnologiaUnidade Local de Saúde de Santo António811-824https://www.ebi.ac.uk/biostudies/studies/S-EPMC12948890biostudies-literatureUnknown126(2)<h4>Purpose</h4>To investigate half-marathon running and recovery effects on knee articular cartilage (KAC) health in athletes, using dictionary-matching T₂ maps, to detect changes and recovery patterns in KAC.<h4>Methods</h4>Eleven asymptomatic volunteers (4 females, 7 males; mean age 40 ± 5 years, mean BMI 22.7 ± 1.4 kg/m²) completed a fixed-pace half-marathonwere studied. All were right-knee dominant and engaged in regular running. Sagittal T₂-weighted Multi-Echo Spin-Echo images at 3 T were used to assess T₂ values pre-run, post-run, and one week later for global and compartmental KAC. Recovery programme included low-intensity running, strength training and rest. Repeated measures ANOVA or equivalent non-parametric tests with post-hoc comparisons compared T₂ values over time. Separate analyses were conducted based on laterality, gender and anatomical compartments. Significance was set at < 0.05.<h4>Results</h4>Post-run T₂ values decreased significantly by 0.9 ms (- 2.0%, p < 0.001), with up to 5.3% reductions in medial tibial (MT) and femoral (MF) compartments. Recovery patterns varied by compartment, sex and laterality. Most compartments returned to baseline within one week; the lateral condyle (LatC) showed incomplete recovery (- 4.7%, Proportional Recovery Index (PRI) = - 0,1); the right knee's MT exhibited overcompensation (6.3%, PRI = 2.6). Males showed higher baseline T₂ values and more efficient recovery in the LatC compared to females (PRI = - 0.1 vs. - 0.4).<h4>Conclusion</h4>Half-marathon running induces reversible reductions in KAC hydration, with most compartments recovering or overcompensating within one week. Dictionary-matching T2 mapping offers a robust approach for monitoring cartilage integrity and guiding individualised recovery strategies.European journal of applied physiologyDetection of physiological changes in knee cartilage using parametric T2 relaxation maps estimated with a dictionary method.PMC1294889010.54499/UIDP/50009/20202020. 05080.BDDOI: 10.54499/LA/P/0083/2020Coelho JMVilaca AFernandes TTOliveira ANogueira LAlves SMNunes RGfalseDetection of physiological changes in knee cartilage using parametric T2 relaxation maps estimated with a dictionary method.<h4>Purpose</h4>To investigate half-marathon running and recovery effects on knee articular cartilage (KAC) health in athletes, using dictionary-matching T₂ maps, to detect changes and recovery patterns in KAC.<h4>Methods</h4>Eleven asymptomatic volunteers (4 females, 7 males; mean age 40 ± 5 years, mean BMI 22.7 ± 1.4 kg/m²) completed a fixed-pace half-marathonwere studied. All were right-knee dominant and engaged in regular running. Sagittal T₂-weighted Multi-Echo Spin-Echo images at 3 T were used to assess T₂ values pre-run, post-run, and one week later for global and compartmental KAC. Recovery programme included low-intensity running, strength training and rest. Repeated measures ANOVA or equivalent non-parametric tests with post-hoc comparisons compared T₂ values over time. Separate analyses were conducted based on laterality, gender and anatomical compartments. Significance was set at < 0.05.<h4>Results</h4>Post-run T₂ values decreased significantly by 0.9 ms (- 2.0%, p < 0.001), with up to 5.3% reductions in medial tibial (MT) and femoral (MF) compartments. Recovery patterns varied by compartment, sex and laterality. Most compartments returned to baseline within one week; the lateral condyle (LatC) showed incomplete recovery (- 4.7%, Proportional Recovery Index (PRI) = - 0,1); the right knee's MT exhibited overcompensation (6.3%, PRI = 2.6). Males showed higher baseline T₂ values and more efficient recovery in the LatC compared to females (PRI = - 0.1 vs. - 0.4).<h4>Conclusion</h4>Half-marathon running induces reversible reductions in KAC hydration, with most compartments recovering or overcompensating within one week. Dictionary-matching T2 mapping offers a robust approach for monitoring cartilage integrity and guiding individualised recovery strategies.2026-01-01T00:00:00Z2026 Feb2026-07-12T03:14:13.353Z2026-07-12T03:11:11.167ZS-EPMC129488904084814510.1007/s00421-025-05898-9