Reopening elite sport during the COVID-19 pandemic: Experiences from a controlled return to elite football in Denmark.

As the SARS-CoV-2 infection rate decreased in spring 2020, phased reopening of Danish society began, including a reopening of elite football (soccer), adhering to a strict protocol. In this study, we report the consequences of resumption of competitive play in the two best football (soccer) leagues for men in Denmark measured by number of SARS-CoV-2 positive players. The players were tested weekly for SARS-CoV-2 for 11 consecutive weeks. The test protocol comprised 26 teams with 748 players. In total, 6511 tests were done with a positivity rate of 0.06%. The incidence rate of players testing positive for SARS-CoV-2 was 0.53% (4/748). There were no signs of a chain of infection. We found a low incidence rate of SARS-CoV-2, and based on this, a controlled reopening of professional football strictly following a detailed protocol appears safe for the players.

Acute high-intensity football games can improve children's inhibitory control and neurophysiological measures of attention.

Recent studies suggest that a single bout of exercise can lead to transient performance improvements in specific cognitive domains in children. However, more knowledge is needed to determine the key exercise characteristics for obtaining these effects and how they translate into real-world settings. In the present study, we investigate how small-sided football games of either high- or moderate-intensity affect measures of inhibitory control in a school setting. Eighty-one children (mean age 11.8, 48 boys) were randomly allocated to three groups performing 20-minute of high-intensity small-sided real football games (SRF), moderate-intensity small-sided walking football games (SWF) or resting (RF). Behavioral measures of inhibitory control and neurophysiological measures of attention (P300 latency and amplitude) were obtained during a flanker task performed at baseline and 20 minutes following the intervention. Retention of declarative memory was assessed in a visual memory task 7 days after the intervention. Measures of inhibitory control improved more in children performing SRF compared to SWF 19 ms, 95% CI [7, 31 ms] (P = 0.041). This was paralleled by larger increases in P300 amplitudes at Fz in children performing SRF compared both to RF in congruent (3.54 µV, 95% CI [0.85, 6.23 µV], P = 0.039) and incongruent trials (5.56 µV, 95% CI [2.87, 8.25 µV], P < 0.001) and compared to SWF in incongruent trials (4.10 µV, 95% CI [1.41, 6.68 µV], P = 0.010). No effects were found in measures of declarative memory. Together this indicates that acute high-intensity small-sided football games can transiently improve measures of inhibitory control and neurophysiological correlates of attention. Intense small-sided football games are easily implementable and can be employed by practitioners, for example, during breaks throughout the school day.

Improved cognitive performance in preadolescent Danish children after the school-based physical activity programme "FIFA 11 for Health" for Europe - A cluster-randomised controlled trial.

OBJECTIVE: Recent studies have shown promising effects of physical activity on cognitive function, but there is a need to investigate this link in real-life settings such as schools. Hence, the objective of the present pilot study was to investigate whether the school-based physical activity programme "FIFA 11 for Health" for Europe could improve cognitive performance in preadolescent Danish children. METHODS: The pilot study used an 11-week cluster-randomised intervention study design. School classes were randomly assigned to either a control group (CG) (n = 93 children, age = 11.8, s = 0.2 years), which performed the obligatory daily school-based physical activity (5 × 45 minutes per week); or an intervention group (IG) (n = 838 children, age = 11.9, s = 0.4 years), which substituted 2 × 45 minutes per week of the daily school physical activity with the "FIFA 11 for Health" for Europe programme. The programme combines small-sided football games, drills and health education. Cognitive performance was evaluated at baseline and follow-up. RESULTS: The IG improved their cognitive performance compared to the CG for psychomotor function (56, sx- = 22 ms, p < .001), attention (39, sx- = 17 ms, p = .012) and working memory (79, sx- = 35 ms, p = .020). CONCLUSION: This pilot study provides evidence that the school-based physical activity programme "FIFA 11 for Health" for Europe can improve cognitive performance in preadolescent Danish schoolchildren. Future studies should attempt to disentangle the effects of "FIFA 11 for Health" for Europe on cognitive performance by investigating the characteristics of the programme's physical activity.

Acute Exercise and Motor Memory Consolidation: The Role of Exercise Timing.

High intensity aerobic exercise amplifies offline gains in procedural memory acquired during motor practice. This effect seems to be evident when exercise is placed immediately after acquisition, during the first stages of memory consolidation, but the importance of temporal proximity of the exercise bout used to stimulate improvements in procedural memory is unknown. The effects of three different temporal placements of high intensity exercise were investigated following visuomotor skill acquisition on the retention of motor memory in 48 young (24.0 ± 2.5 yrs), healthy male subjects randomly assigned to one of four groups either performing a high intensity (90% Maximal Power Output) exercise bout at 20 min (EX90), 1 h (EX90+1), 2 h (EX90+2) after acquisition or rested (CON). Retention tests were performed at 1 d (R1) and 7 d (R7). At R1 changes in performance scores after acquisition were greater for EX90 than CON (p < 0.001) and EX90+2 (p = 0.001). At R7 changes in performance scores for EX90, EX90+1, and EX90+2 were higher than CON (p < 0.001, p = 0.008, and p = 0.008, resp.). Changes for EX90 at R7 were greater than EX90+2 (p = 0.049). Exercise-induced improvements in procedural memory diminish as the temporal proximity of exercise from acquisition is increased. Timing of exercise following motor practice is important for motor memory consolidation.