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Individual preference and tolerance can be seen as relevant traits for the understanding of the relationship between exercise intensity and behavioral outcomes. To better understand that relationship, this scoping review aimed to analyze preference for, and tolerance of, exercise intensity constructs in physical activity settings by verifying the contextual utility and feasibility of the subscales in the multiple settings of their application, the interpretation of the subscales, associations with other variables, and the reported limitations of the subscales’ use. The search was conducted through PubMed, SPORTDiscus, PsycINFO, and B-on databases. Inclusion criteria were healthy individuals including athletes, experimental and nonexperimental studies written in English based on the assessment of subjective intensity in exercise; studies including the variables tolerance and/or preference. Exclusion criteria were instrument validation studies with no concurrent data, gray literature, and systematic reviews. Thirty-six studies published between 2005 and 2022 were analyzed. Results indicate that both constructs appear to be useful and feasible in various physical activity settings. No relevant limitations were reported for its use. Preference and tolerance constructs assessed with the PRETIE-Q (Preference for and Tolerance of the Intensity of Exercise Questionnaire) seem to offer a simple but useful understanding of the individual relation with exercise intensity in several physical activity–related outcomes.

Background: COVID-19 caused closures of movement supporting environments such as gyms and schools in Canada. This study evaluated the association between Ontario parents’ and children’s physical activity levels across time during COVID-19, controlling for variables that were identified as significant predictors of children’s and parents’ physical activity (e.g., children’s age, parents’ employment status). Methods: Parents (n = 243; mean age = 38.8 y) of children aged 12 and under (n = 408; mean age = 6.3 y) living in Ontario, Canada completed 2 online surveys, the first between August and December 2020 and the second between August and December 2021. At baseline, parents were asked to recall prepandemic physical activity levels. To determine the association between parent and child physical activity during COVID-19, a cross-lagged model was estimated to determine the cross-sectional and longitudinal associations between parents’ and children’s physical activity across time. Results: Bivariate associations revealed that parents’ and children’s physical activity levels were significantly related during lockdown and postlockdown but not prelockdown. The autoregressive paths from prelockdown to during lockdown were significant for children (β = 0.53, P < .001) and parents (β = 1.058, P < .001) as were the autoregressive paths from during lockdown to postlockdown for children (β = 0.61, P < .001) and parents (β = 0.48, P < .001). In fully adjusted models, the cross-lagged association between parents’ physical activity prelockdowns was significantly positively associated with their children’s physical activity during lockdowns (β = 0.19, P = .013). Conclusions: Resources are needed to ensure that children and parents are obtaining sufficient levels of physical activity, particularly during a pandemic.

Purpose: This study determined the evolution of performance and pacing for each winner of the men’s Olympic 1500-m running track final from 1924 to 2020. Methods: Data were obtained from publicly available sources. When official splits were unavailable, times from sources such as YouTube were included and interpolated from video records. Final times, lap splits, and position in the peloton were included. The data are presented relative to 0 to 400 m, 400 to 800 m, 800 to 1200 m, and 1200 to 1500 m. Critical speed and D′ were calculated using athletes’ season’s best times. Results: Performance improved ∼25 seconds from 1924 to 2020, with most improvement (∼19 s) occurring in the first 10 finals. However, only 2 performances were world records, and only one runner won the event twice. Pacing evolved from a fast start–slow middle–fast finish pattern (reverse J-shaped) to a slower start with steady acceleration in the second half (J-shaped). The coefficient of variation for lap speeds ranged from 1.4% to 15.3%, consistent with a highly tactical pacing pattern. With few exceptions, the eventual winners were near the front throughout, although rarely in the leading position. There is evidence of a general increase in both critical speed and D′ that parallels performance. Conclusions: An evolution in the pacing pattern occurred across several “eras” in the history of Olympic 1500-m racing, consistent with better trained athletes and improved technology. There has been a consistent tactical approach of following opponents until the latter stages, and athletes should develop tactical flexibility, related to their critical speed and D′, in planning prerace strategy.

Background: Physical activity (PA) is essential for optimal diabetes management. Household food insecurity (HFI) may negatively affect diabetes management behaviors. The purpose of this study was to cross-sectionally examine the association between HFI and PA in youth and young adults (YYA) with type 1 (N = 1998) and type 2 (N = 391) diabetes from the SEARCH for Diabetes in Youth Study. Methods: HFI was measured with the US Household Food Security Survey Module. PA was measured with the International Physical Activity Questionnaire Short Form. Walking, moderate-intensity PA (excluding walking), vigorous-intensity PA, moderate- to vigorous-intensity PA, and total PA were estimated as minutes per week, while time spent sitting was assessed in minutes per day. All were modeled with median regression. Meeting PA guidelines or not was modeled using logistic regression. Results: YYA with type 1 diabetes who experienced HFI spent more time walking than those who were food secure. YYA with type 2 diabetes who experienced HFI spent more time sitting than those who were food secure. Conclusions: Future research should examine walking for leisure versus other domains of walking in relation to HFI and use objective PA measures to corroborate associations between HFI and PA in YYA with diabetes.

We have previously shown evidence that some individuals seem to consistently minimize low back loads when lifting, while others do not. However, it is unknown why. Individual differences in ability to perceive relevant sensory information may explain differences in minimization of low back loads during lifting, consistent with considering load reduction in one’s movement objective in an optimal feedback control theory framework. The purpose of this study was to investigate whether individuals’ ability to perceive proprioceptive information (both force- and posture-senses) at the low back was associated with peak low back loads when performing generic or occupation-specific lifts. Seventy-two participants were recruited to perform 10 barbell (generic) and backboard (occupation-specific) lifts, while whole-body kinematics and ground reaction forces were collected. Peak low back compression and anteroposterior shear forces normalized to body mass were calculated as dependent variables. Both posture matching ability and force matching ability at the heavier force targets were associated with lower means and variability of peak low-back loads in both lift types, albeit with small effect sizes (R ² ≤ .17). These findings support the utility of an optimal feedback control theory framework to explore factors explaining interindividual differences in low back loads during lifting. Further, this evidence suggests improving proprioceptive ability may be a useful strategy in lift training programs designed for workplace injury prevention.

Previous studies showed that collagen peptide supplementation along with resistance exercise enhance muscular recovery and function. Yet, the efficacy of collagen peptide supplementation in addition to standard nutritional practices in athletes remains unclear. Therefore, the objective of the study was to compare the effects of combined collagen peptide (20 g) and whey protein (25 g) supplementation with a similar daily protein dose (45 g) of whey protein alone on indices of muscle damage and recovery of muscular performance during eccentric exercise training. Young fit males participated in a 3-week training period involving unilateral eccentric exercises for the knee extensors. According to a double-blind, randomized, parallel-group design, before and after training, they received either whey protein (n = 11) or whey protein + collagen peptides (n = 11). Forty-eight hours after the first training session, maximal voluntary isometric and dynamic contraction of the knee extensors were transiently impaired by ∼10% (P _time < .001) in whey protein and whey protein + collagen peptides, while creatine kinase levels were doubled in both groups (P _time < .01). Furthermore, the training intervention improved countermovement jump performance and maximal voluntary dynamic contraction by respectively 8% and 10% (P _time < .01) and increased serum procollagen type 1N-terminal peptide concentration by 10% (P _time < .01). However, no differences were found for any of the outcomes between whey and whey protein + collagen peptides. In conclusion, substituting a portion of whey protein for collagen peptide, within a similar total protein dose, improved neither indices of eccentric muscle damage nor functional outcomes during eccentric training.