Purpose: To investigate the sensitivity of differential ratings of perceived exertion (dRPE) as measures of internal load.Methods: Twenty-two male university soccer players performed 2 maximal incremental-exercise protocols (cycle, treadmill) on separate days. Maximal oxygen uptake (V̇O_2max), maximal heart rate (HR_max), peak blood lactate concentration (B[La]_peak), and the preprotocol-to-postprotocol change in countermovement-jump height (ΔCMJ_H) were measured for each protocol. Players provided dRPE (CR100) for breathlessness (RPE-B) and leg-muscle exertion (RPE-L) immediately on exercise termination (RPE-B₀, RPE-L₀) and 30 min postexercise (RPE-B₃₀, RPE-L₃₀). Data were analyzed using magnitude-based inferences.Results: There were clear between-protocols differences for V̇O_2max (cycle 46.5 ± 6.3 vs treadmill 51.0 ± 5.1 mL · kg⁻¹ · min⁻¹, mean difference –9.2%; ±90% confidence limits 3.7%), HR_max (184.7 ± 12.7 vs 196.7 ± 7.8 beats/min, –6.0%; ±1.7%), B[La]_peak (9.7 ± 2.1 vs 8.5 ± 2.0 mmol/L, 15%; ±10%), and ΔCMJ_H (–7.1 ± 4.2 vs 0.6 ± 3.6 cm, –23.2%; ±5.4%). Clear between-protocols differences were recorded for RPE-B₀ (78.0 ± 11.7 vs 94.7 ± 9.5 AU, –18.1%; ±4.5%), RPE-L₀ (92.6 ± 9.7 vs 81.3 ± 14.1 AU, 15.3%; ±7.6%), RPE-B₃₀ (70 ± 11 vs 82 ± 13 AU, –13.8%; ±7.3%), and RPE-L₃₀ (86 ± 12 vs 65 ± 19 AU, 37%; ±17%). A substantial timing effect was observed for dRPE, with moderate to large reductions in all scores 30 min postexercise compared with scores collected on exercise termination.Conclusion: dRPE enhance the precision of internal-load measurement and therefore represent a worthwhile addition to training-load-monitoring procedures.

Competence in fundamental movement skills is essential to enable children to be physically active. We investigated the effect of an integrated fundamental movement skill with a strength training intervention on children’s fundamental movement skills. Seventy-two (53% female) 10- to 11-year-old children from three primary schools assented to take part in this study (87% compliance). Schools were randomly allocated to a control (no intervention; n = 21), fundamental movement skill (FMS) (n = 18) or FMS and strength (FMS⁺; n = 20) group. Interventions were delivered twice weekly for four weeks, in addition to normal physical education. FMS competence was measured through the Canadian agility and movement skills assessment (CAMSA) (product-process) and through countermovement jump (CMJ) and 40-m sprint tests (product). Improvements were observed in the CAMSA in both FMS (4.6, 95% confidence intervals 2.9 to 6.4 Arbitrary Units (AUs), second-generation p-value (p_δ) = 0.03) and FMS⁺ (3.9, 2.1 to 5.3 AU, p_δ = 0.28) with no difference beyond our minimum threshold of 3 AU observed between these intervention groups (p_δ = 1). Clear improvements in CMJ were observed in FMS⁺ relative to the control (25, 18 to 32%, p_δ = 0) and FMS groups (15, 6.1 to 24%, p_δ = 0). These preliminary data suggest combined FMS and strength training warrants further investigation as a tool to develop fundamental movement skills in children.

The school playground can promote PA for large numbers of children. This study identifies areas of the playground that children visited at break-times, the decisions according to gender and the influence of contextual and environmental variables on PA levels. The playground of a culturally diverse primary school was observed during morning break-times and lunchtimes. Counts of sedentary, LPA, and MVPA episodes, and the contexts in which they occurred were recorded using the system for observing play and leisure in youth (SOPLAY). Ball sports areas had higher counts of boys (mean ± SD; 9.9 ± 4.8) compared to girls (2.0 ± 3.5); areas promoting climbing and social interaction had higher counts of girls (7.9 ± 7.2) compared to boys (3.5 ± 2.9). The proportion of MVPA episodes during break-times was 34% ± 26%. Areas of the playground with organised activities had 2.70 (95%CI: 1.87 to 3.91) times higher MVPA counts than areas “not organised”. Areas with “supervision” were associated with higher MVPA counts (1.34; 1.18 to 1.53) compared with “not supervised” areas. Organisation and supervision might influence PA choices and PA levels of children in the primary school playground. Further investigation is required to explore different playgrounds settings, and context and gender preferences.

Introduction:The efficacy of high-intensity interval training (HIIT) for improving markers of physical fitness and cardiometabolic health is promising. The workplace is one non-laboratory setting where the effectiveness of HIIT could be explored. The aim of this study was to undertake a mixed-methods exploratory pilot trial of a workplace HIIT intervention named Brief Exercise at Work (BE@Work).Methods:Fifty-four healthy employees (mean ± standard deviation [SD] age 46 ± 10 years) from two workplaces in Northeast England were allocated to 8 weeks of thrice-weekly workplace HIIT based on boxing, stair climbing and stepping, comprising 4–7 60 s high-intensity intervals interspersed with 75 s rest (n= 30), or a no-intervention control (n= 24). The primary outcome was the change SD of predicted maximal oxygen consumption (VO_2max). Markers of physical fitness, cardiometabolic health and mental well-being were also measured at baseline and follow-up. Participant perceptions of the intervention were explored in post-intervention focus groups (n= 9).Results:Mean (±SD) session attendance was 82% (±15%). Mean peak heart rate across the intervention was 87% of age-predicted maximal heart rate with a within- and between-subject SD of 5.5% and 3.7%, respectively. The SD of changes in predicted VO_2maxwas 6.6 mL·kg⁻¹·min⁻¹across both groups, which can be used to inform sample size estimations for a future full trial. The control-adjusted mean increase (95% confidence interval) in predicted VO_2maxwas 3.9 (−0.2 to 8.1) mL·kg⁻¹·min⁻¹, corresponding to a Cohen's D of 0.47. We also observed preliminary evidence of small to moderate effects in favour of the intervention group for non-dominant leg extensor muscle power, markers of health-related quality of life, well-being and perceived stress and small to moderate effects in favour of the controls in perceived pain, physical activity and high-density lipoprotein cholesterol. During HIIT, focus group participants reported physiological responses they perceived as unpleasant or tiring (e.g., breathlessness, local muscular fatigue), but also that they felt alert and energised afterwards.Conclusion:The findings of this exploratory pilot trial support the implementation of a definitive randomised controlled trial to quantify the effectiveness of a workplace HIIT intervention.

Ultra-running comprises running events longer than a marathon (>42.2 km). The prolonged duration of ultra-running leads to decrements in most or all physiological parameters and considerable energy expenditure (EE) and energy deficits. SG, 47 years, 162.5 cm, 49 kg, VO_2max 4 mL/kg/min⁻¹/2.37 L/min⁻¹, ran continuously for 7 days on a treadmill in 3 h blocks followed by 30 min breaks and slept from 1–5 a.m. Heart rate (HR) oxygen uptake (VO₂), rating of perceived exertion, weight, blood lactate (mmol·L⁻¹), haemoglobin (g·dL), haematocrit (%) and glucose (mmol·L⁻¹), and nutrition and hydration were recorded. SG ran for 17.5 h/day, covering ~120 km/day at ~7 km/h. Energy expenditure for each 24 h period was 6878 kcal/day and energy intake (EI) was 2701 kcal/day. EE was 382 kcal/h, with 66.6% from fat and 33.4% from carbohydrate oxidation. 7 day EI was 26,989 kcal and EE was 48,147 kcal, with a total energy deficit (ED) of 21,158 kcal. Average VO₂ was 1.2 L·min⁻¹/24.7 mL·kg·min⁻¹, Respriatory echange ratio (RER) 0.80 ± 0.03, HR 120–125 b·min⁻¹. Weight increased from 48.6 to 49.5 kg. Haemoglobin decreased from 13.7 to 11 g·dL and haematocrit decreased from 40% to 33%. SG ran 833.05 km. SG exhibits an enhanced fat metabolism through which she had a large daily ED. Her success can be attributed to a combination of physiological and psychological factors.