Maximal Strength, Sprint, and Jump Performance in High-Level Female Football Players Are Maintained With a Customized Training Program During the COVID-19 Lockdown

Abstract

IntroductionThe COVID-19 outbreak with partial lockdown has inevitably led to an alteration in training routines for football players worldwide. Thus, coaches had to face with the novel challenge of minimizing the potential decline in fitness during this period of training disruption.MethodsIn this observational pre- to posttest study involving Norwegian female football players (18.8 ± 1.9 years, height 1.68 ± 0.4 m, mass 61.3 ± 3.7 kg), we investigated the effects of a prescribed home-based and group-based intervention, implemented during the COVID-19 lockdown, on maximal muscular force production and high velocity variables. Specifically, maximal partial squat strength one repetition maximum (1RM), counter movement jump (CMJ) and 15 m sprint time were assessed 1 week prior to the lockdown and 12 weeks after the onset of lockdown. We also collected training content and volume from the prescribed training program and self-reported perceived training quality and motivation toward training.ResultsWe observed no change in 1RM [pretest: 104 ± 12 kg, posttest: 101 ± 11 kg (P = 0.28)], CMJ height [pretest: 28.1 ± 2.3 cm, posttest: 26.8 ± 1.9 (P = 0.09)], and 15 m sprint time [pretest: 2.60 ± 0.08 s, posttest: 2.61 ± 0.07 s (P = 0.52)].ConclusionOur findings suggest that a prescribed home-based and group-based intervention with increased training time devoted to strength, jump, and sprint ability, and regulated to obtain a sufficient infection control level is feasible and effective to preserve strength, jumping, and sprinting abilities of high-level female football players during a ∼ 3-month period of a pandemic-induced lockdown.

The Effects of a Five-Month Lockdown Due to COVID-19 on Physical Fitness Parameters in Adolescent Students: A Comparison between Cohorts

“…On the other hand, Spyrou et al [ 23 ] did not observe significant differences in vertical jump after 70 days of quarantine in futsal elite players. These discrepancies in vertical jumping ability in students compared with athletes may be that athletes even in the case of lockdowns and quarantines were obliged to train at home [ 42 ]. In the present study we also observed that flexibility of lower back and hamstrings, measured by the sit-and-reach test, was significantly lower only in males after the 5-month lockdown compared with the previous cohorts.…”

Auswirkungen des COVID-19-Lockdowns auf physische Leistungsparameter im professionellen Fußball

“…Vier Studien [ 6 , 7 , 10 , 20 ] verglichen die Leistungsfähigkeit der Fußballspielenden mit Leistungsdaten aus vorherigen Spielzeiten. Zwei Studien [ 1 , 16 ] ermittelten die Leistungsfähigkeit der Sportler/-innen unmittelbar vor und nach der Lockdownperiode. Die Maßnahmen zur Eindämmung des Coronavirus variierten zwischen den Ländern und Regionen der einzelnen Studien und werden daher bei Erstnennung kurz erläutert.…”

“… Squat Jumps und Counter Movement Jumps auf einer Kontaktplattform Sprunghöhe SJ (cm) Nordic-Hamstring-Curl mit Kraftaufnahme (exzentrische Kniebeuger) Messwerte der Kraftleistung: Sprint mittels Lichtschrankenmessung bei Start, 10 m und 20 m Absolute Kraft (N) Statistik: Relative Kraft (N/kg) t‑Test für verbundene Stichproben, Effektstärke Messwert der Sprintleistung: 10 m Sprintzeit (s; 6,9 % ) 20 m Sprintzeit (s; 4,3 % ) Pedersen et al. (2021) [ 16 ] 8 professionelle Fußballspielerinnen (Norwegen, Level 3) Dauer: 12 Wochen Design: Messwert der Kraftleistung: Alter: 18,8 ± 1,9 Jahre; Größe 168 ± 4 cm; Gewicht 61,3 ± 3,7 kg Wöchentliche Trainingszeit: 233 ± 47 min Prä- vs. Post-COVID-19 Einerwiederholungsmaximum (kg) Heimtraining: 4 Wochen Heimtraining Messwerte der Sprungleistung: Individuelles und kontaktloses Gruppentraining bestehend aus Kraft‑, Schnelligkeit‑, Sprung- und Laufübungen 8 Wochen kontaktloses Kleingruppentraining ohne Equipment Sprunghöhe (cm) Datenerhebung: Absprunggeschwindigkeit (ms) Kniebeugen Maximale und mittlere Kraft (N) Contermovement-Jumps auf Kraftmessplatte Maximale und mittlere Leistung (W) Sprint mittels Lichtschrankenmessung bei Start, 5 m, 10 m und 15 m Flugzeit (ms) Statistik: Messwert der Sprintleistung: t‑Test für verbundene Stichproben 5 m, 10 m & 15 m Sprintzeit (s) Cohen et al. (2020) [ 7 ] 16 professionelle Fußballspieler der 1. kolumbianischen Liga Dauer: 15 Wochen Design: Messwerte der Sprungleistung: Alter: 24,3 ± 3,8 Jahre; Größe: 179 ± 7 cm; Gewicht: 79,2 ± 9 kg Häufigkeit: 5‑ bis 6‑mal/Woche Prä- vs. Post-COVID-19-Quarantäne im Vergleich zu einer weiteren Prä-Post-Periode der Saisonp...…”

“…Zwei der eingeschlossenen Untersuchungen [ 10 , 16 ] erfassten die Kraftleistung der Fußballspielenden im Zuge des Lockdowns mittels des Einwiederholungsmaximums der Kniebeuge bzw. der exzentrischen Kraft im Nordic-Hamstring-Curl.…”

Exercise-Based Injury Prevention in High-Level and Professional Athletes: Narrative Review and Proposed Standard Operating Procedure for Future Lockdown-Like Contexts After COVID-19

“…These will include muscle strengthening, flexibility, neuromuscular control, balance and agility, core stability, plyometrics, sport-specific movements (of uttermost importance) and endurance in varying degrees according to the sport concerned. The balance between endurance or strength training and sport-specific training will have to be adapted as to compensate the reduced sport-specific training while maintaining overall fitness (Pedersen et al, 2021) (Balsalobre-Fernández et al, 2015Lim, 2020) and further development of these "tele-screening" approaches should be encouraged. Continuous monitoring of both training load and athlete wellbeing would be further recommended to individually tailor an optimal training.…”