title: Recovery kinetics of knee flexor and extensor strength after a football match.
abstract: We examined the temporal changes of isokinetic strength performance of knee flexor (KF) and extensor (KE) strength after a football match. Players were randomly assigned to a control (N = 14, participated only in measurements and practices) or an experimental group (N = 20, participated also in a football match). Participants trained daily during the two days after the match. Match and training overload was monitored with GPS devices. Venous blood was sampled and muscle damage was assessed pre-match, post-match and at 12 h, 36 h and 60 h post-match. Isometric strength as well as eccentric and concentric peak torque of knee flexors and extensors in both limbs (dominant and non-dominant) were measured on an isokinetic dynamometer at baseline and at 12 h, 36 h and 60 h after the match. Functional (KFecc/KEcon) and conventional (KFcon/KEcon) ratios were then calculated. Only eccentric peak torque of knee flexors declined at 60 h after the match in the control group. In the experimental group: a) isometric strength of knee extensors and knee flexors declined (P<0.05) at 12 h (both limbs) and 36 h (dominant limb only), b) eccentric and concentric peak torque of knee extensors and flexors declined (P<0.05) in both limbs for 36 h at 60°/s and for 60 h at 180°/s with eccentric peak torque of knee flexors demonstrating a greater (P<0.05) reduction than concentric peak torque, c) strength deterioration was greater (P<0.05) at 180°/s and in dominant limb, d) the functional ratio was more sensitive to match-induced fatigue demonstrating a more prolonged decline. Discriminant and regression analysis revealed that strength deterioration and recovery may be related to the amount of eccentric actions performed during the match and athletes' football-specific conditioning. Our data suggest that recovery kinetics of knee flexor and extensor strength after a football match demonstrate strength, limb and velocity specificity and may depend on match physical overload and players' physical conditioning level.
authors.affiliation: School of Physical Education and Sports Science, Democritus University of Thrace, Komotini, Greece.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Draganidis
authors.affiliation: School of Physical Education and Sports Science, Democritus University of Thrace, Komotini, Greece.
authors.forename: Athanasios
authors.initials: A
authors.lastname: Chatzinikolaou
authors.affiliation: School of Physical Education and Sports Science, Democritus University of Thrace, Komotini, Greece.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Avloniti
authors.affiliation: University of Granada, Campus of Melilla, Melilla, Spain.
authors.forename: José C
authors.initials: JC
authors.lastname: Barbero-Álvarez
authors.affiliation: Faculty of Natural and Health Science, University of the Faroe Islands, Tórshavn, Faroe Islands; Centre of Health and Human Performance, Department of Food and Nutrition, and Sport Sciences, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Magni
authors.initials: M
authors.lastname: Mohr
authors.affiliation: School of Physical Education and Sports Science, Democritus University of Thrace, Komotini, Greece.
authors.forename: Paraskevi
authors.initials: P
authors.lastname: Malliou
authors.affiliation: School of Physical Education and Sports Science, Democritus University of Thrace, Komotini, Greece.
authors.forename: Vassilios
authors.initials: V
authors.lastname: Gourgoulis
authors.affiliation: School of Physical Education and Sports Science, University of Thessaly, Trikala, Greece.
authors.forename: Chariklia K
authors.initials: CK
authors.lastname: Deli
authors.affiliation: School of Physical Education and Sports Science, Democritus University of Thrace, Komotini, Greece.
authors.forename: Ioannis I
authors.initials: II
authors.lastname: Douroudos
authors.affiliation: School of Physical Education and Sports Science, Democritus University of Thrace, Komotini, Greece.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Margonis
authors.affiliation: School of Physical Education and Sports Science, Democritus University of Thrace, Komotini, Greece.
authors.forename: Asimenia
authors.initials: A
authors.lastname: Gioftsidou
authors.forename: Andreas D
authors.initials: AD
authors.lastname: Flouris
authors.affiliation: School of Physical Education and Sports Science, University of Thessaly, Trikala, Greece; Institute of Human Performance and Rehabilitation, Centre for Research and Technology, Thessaly (CERETETH), Trikala, Greece.
authors.forename: Andreas D
authors.initials: AD
authors.lastname: Fouris
authors.affiliation: School of Physical Education and Sports Science, University of Thessaly, Trikala, Greece; Institute of Human Performance and Rehabilitation, Centre for Research and Technology, Thessaly (CERETETH), Trikala, Greece.
authors.forename: Athanasios Z
authors.initials: AZ
authors.lastname: Jamurtas
authors.affiliation: School of Physical Education and Sports Science, University of Thessaly, Trikala, Greece; Institute of Human Performance and Rehabilitation, Centre for Research and Technology, Thessaly (CERETETH), Trikala, Greece; School of Sports, Performing Arts and Leisure, University of Wolverhampton, Wolverhampton, United Kingdom.
authors.forename: Yiannis
authors.initials: Y
authors.lastname: Koutedakis
authors.affiliation: School of Physical Education and Sports Science, Democritus University of Thrace, Komotini, Greece; School of Physical Education and Sports Science, University of Thessaly, Trikala, Greece.
authors.forename: Ioannis G
authors.initials: IG
authors.lastname: Fatouros
mesh_terms: D054874:Athletic Performance; D005121:Extremities / Q000502:physiology; D005538:Football; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007700:Kinetics; D007717:Knee / Q000502:physiology*; D016014:Linear Models; D008297:Male; D009043:Motor Activity; D018482:Muscle, Skeletal / Q000473:pathology; D013997:Time Factors; D055815:Young Adult