Executive function skills play a critical role in school readiness for young children and can be improved through targeted intervention. However, children in preschool often experience deficits in multiple developmental domains. Thus, there is a need for integrated interventions that target multiple domains in concert. This study tested whether a proven gross motor skill intervention, Successful Kinesthetic Instruction for Preschoolers (SKIP), also improves preschoolers’ executive function. Participants were randomly assigned to either intervention (n = 50) or control (n = 57) conditions. Prior to intervention, executive function and gross motor skills were tested. Intervention occurred for 6 weeks with 30-min sessions twice weekly (dose = 360 min). At posttest, participants in the SKIP condition showed significantly better gross motor and executive function skills than control participants. Results are the first to document the effectiveness of the SKIP intervention in also improving children’s executive function.
Kelly Lynn Mulvey, Sally Taunton, Adam Pennell and Ali Brian
Durva Vahia, Adam Kelly, Harry Knapman and Craig A. Williams
Purpose: When exposed to the same external load, players receive different internal loads, resulting in varied adaptations in fitness. In adult soccer, internal training load is measured using heart rate (HR) and session rating of perceived exertion (sRPE) scales, but these have been underutilized in youth soccer. This study investigated the in-season variation in correlation between HR and sRPE estimations of training load for adolescent soccer players. Method: Fifteen male professional adolescent players were monitored for 7 months. Within-participant correlations and Bland–Altman agreement plots for HR and sRPE were calculated for each month to analyze variation over the season and for individual players to analyze the validity of the scale. Results: The monthly correlations ranged from r = .60 to r = .73 (P < .05) and the overall correlation was r = .64 (95% confidence interval, .60–.68; P < .001). Bland–Altman plots showed an agreement of methods. Conclusion: Results showed consistently large correlations for all months. sRPE is a consistent method of measure of internal training load for the entire season for youth soccer players. Validity analysis found no bias in sRPE measurements when compared with HR for all players in the study.
Lindsay B. Baker, Kelly A. Barnes, Bridget C. Sopeña, Ryan P. Nuccio, Adam J. Reimel and Corey T. Ungaro
The purpose of this study was to determine the effect of storage temperature on sodium ([Na+]), potassium ([K+]), and chloride ([Cl−]) concentrations of sweat samples analyzed 7 days after collection. Using the absorbent patch technique, 845 sweat samples were collected from 39 subjects (32 ± 7 years, 72.9 ± 10.5 kg) during exercise. On the same day as collection (PRESTORAGE), 609 samples were analyzed for [Na+], [Cl−], and [K+] by ion chromatography (IC) and 236 samples were analyzed for [Na+] using a compact ion-selective electrode (ISE). Samples were stored at one of the four conditions: −20 °C (IC, n = 138; ISE, n = 60), 8 °C (IC, n = 144; ISE, n = 59), 23 °C (IC, n = 159; ISE, n = 59), or alternating between 8 °C and 23 °C (IC, n = 168; ISE, n = 58). After 7 days in storage (POSTSTORAGE), samples were reanalyzed using the same technique as PRESTORAGE. PRESTORAGE sweat electrolyte concentrations were highly related to that of POSTSTORAGE (intraclass correlation coefficient: .945–.989, p < .001). Mean differences (95% confidence intervals) between PRESTORAGE and POSTSTORAGE were statistically, but not practically, significant for most comparisons: IC [Na+]: −0.5(0.9) to −2.1(0.9) mmol/L; IC [K+]: −0.1(0.1) to −0.2(0.1) mmol/L; IC [Cl−]: −0.4(1.4) to −1.3(1.3) mmol/L; ISE [Na+]: −2.0(1.1) to 1.3(1.1) mmol/L. Based on typical error of measurement results, 95% of the time PRESTORAGE and POSTSTORAGE sweat [Na+], [K+], and [Cl−] by IC analysis fell within ±7–9, ±0.6–0.7, and ±9–13 mmol/L, respectively, while sweat [Na+] by ISE was ±6 mmol/L. All conditions produced high reliability and acceptable levels of agreement in electrolyte concentrations of sweat samples analyzed on the day of collection versus after 7 days in storage.
Samuel G. Impey, Kelly M. Hammond, Robert Naughton, Carl Langan-Evans, Sam O. Shepherd, Adam P. Sharples, Jessica Cegielski, Kenneth Smith, Stewart Jeromson, David L. Hamilton, Graeme L. Close and James P. Morton
We examined the effects of whey versus collagen protein on skeletal muscle cell signaling responses associated with mitochondrial biogenesis and protein synthesis in recovery from an acute training session completed with low carbohydrate availability. In a repeated-measures design (after adhering to a 36-hr exercise–dietary intervention to standardize preexercise muscle glycogen), eight males completed a 75-min nonexhaustive cycling protocol and consumed 22 g of a hydrolyzed collagen blend (COLLAGEN) or whey (WHEY) protein 45 min prior to exercise, 22 g during exercise, and 22 g immediately postexercise. Exercise decreased (p < .05) muscle glycogen content by comparable levels from pre- to postexercise in both trials (≈300–150 mmol/kg·dry weight). WHEY protein induced greater increases in plasma branched chain amino acids (p = .03) and leucine (p = .02) than COLLAGEN. Exercise induced (p < .05) similar increases in PGC-1α (fivefold) mRNA at 1.5 hr postexercise between conditions, although no effect of exercise (p > .05) was observed for p53, Parkin, and Beclin1 mRNA. Exercise suppressed (p < .05) p70S6K1 activity in both conditions immediately postexercise (≈25 fmol·min−1·mg−1). Postexercise feeding increased p70S6K1 activity at 1.5 hr postexercise (p < .05), the magnitude of which was greater (p < .05) in WHEY (180 ± 105 fmol·min−1·mg−1) versus COLLAGEN (73 ± 42 fmol·min−1·mg−1). We conclude that protein composition does not modulate markers of mitochondrial biogenesis when in recovery from a training session deliberately completed with low carbohydrate availability. By contrast, whey protein augments postexercise p70S6K activity compared with hydrolyzed collagen, as likely mediated via increased leucine availability.