BACKGROUND: The Neurotracker CORE assessment is an 8-minute multiple object tracking (MOT) program used in sport science research and clinical rehabilitation as a perceptual-cognitive training tool; however, it has garnered interest for its potential use as an acute assessment of cognitive performance. Although some data exist regarding the learning effect of repeated exposures, it is often overlooked with investigators focusing primarily on the presence of transfer effects to other cognitive realms. As a result, exclusive data on the effect of repeated testing, or subsequent periods of no testing (ie, detraining) on test-retest reliability, and on MOT performance are sparse.
METHODS: Repeated-measures/reliability.
METHODS: Twenty-three recreationally active men and women completed 15 training sessions consisting of 2 CORE assessments per session (30 assessments). Participants were randomized to either 1 or 2 weeks of detraining prior to completing 15 retraining sessions (30 assessments). Training and retraining periods were divided into 10 blocks (3 assessments/block) for analysis. MOT speed threshold (MOT-ST), consistency, fastest trial score success speed, lowest trial score miss speed, the number of perfect, near misses, and significant miss trials within each block were used to determine performance. Intraclass correlation coefficient, standard error of measurement, and minimal detectable change were used to determine reliability.
RESULTS: Significant improvements in MOT-ST and fastest trial score success speed were noted within training blocks 1 to 6 and 1 to 7, respectively (P < .05). MOT-ST and fastest trial score success speed demonstrated excellent test-retest reliability between blocks 8 and 9. There was no effect of detraining period on performance during retraining.
CONCLUSIONS: Eighteen tests are necessary to overcome training effects and establish a reliable baseline when MOT-ST is used as the performance outcome. Detraining periods up to 2 weeks did not impact performance. The average of 3 discrete tests should be used when assessing MOT-ST performance.

BACKGROUND: It is not known whether an intervention made mandatory as a physical education (PE) class assignment and aimed at promoting physical activity (PA) in adolescents can create a healthy walking habit, which would allow further improvements to be achieved after the mandatory and promoted intervention has been completed.
OBJECTIVE: The aims of this study were to (1) investigate whether, after a period of using a step tracker mobile app made mandatory and promoted as a PE class assignment, adolescents continue to use it when its use is no longer mandatory and promoted; (2) determine whether there are changes in the PA level, body composition, and fitness of adolescents when the use of the app is mandatory and promoted and when it is neither mandatory nor promoted; and (3) analyze whether the covariates maturity status, gender, and specific app used can have an influence.
METHODS: A total of 357 students in compulsory secondary education (age: mean 13.92, SD 1.91 y) participated in the study. A randomized controlled trial was conducted consisting of 2 consecutive 10-week interventions. Participants\' PA level, body composition, and fitness were measured at baseline (T1), after 10 weeks of mandatory and promoted app use (T2), and after 10 weeks of nonmandatory and nonpromoted app use (T3). Each participant in the experimental group (EG) used 1 of 4 selected step tracker mobile apps after school hours.
RESULTS: The results showed that when the use of the apps was neither mandatory nor promoted as a PE class assignment, only a few adolescents (18/216, 8.3%) continued the walking practice. After the mandatory and promoted intervention period (T1 vs T2), a decrease in the sum of 3 skinfolds (mean difference [MD] 1.679; P=.02) as well as improvements in the PA level (MD -0.170; P<.001), maximal oxygen uptake (MD -1.006; P<.001), countermovement jump test (MD -1.337; P=.04), curl-up test (MD -3.791; P<.001), and push-up test (MD -1.920; P<.001) in the EG were recorded. However, the changes between T1 and T2 were significantly greater in the EG than in the control group only in the PA level and curl-up test. Thus, when comparing the measurements taken between T1 and T3, no significant changes in body composition (P=.07) or fitness (P=.84) were observed between the EG and the control group. The covariates maturity status, gender, and specific app used showed a significant effect in most of the analyses performed.
CONCLUSIONS: A period of mandatory and promoted use of step tracker mobile apps benefited the variables of body composition and fitness in adolescents but did not create a healthy walking habit in this population; therefore, when the use of these apps ceased to be mandatory and promoted, the effects obtained disappeared.
BACKGROUND: ClinicalTrials.gov NCT06164041; https://clinicaltrials.gov/study/NCT06164041.

The aim of the study was to investigate the effect of two long-term reduced concurrent training modalities, in which participants performed one training session every either 7 or 14 days, after 12 weeks of systematic concurrent resistance and aerobic training, on lower extremities\' muscle strength, power, and morphology in young females. After the 12-week training period, participants were assigned into three groups and performed either one training session every 7 days (G7) or once every 14 days (G14), or detraining (GD), for 12 weeks, followed by 12 additional weeks of detraining. The following were measured before, after the systematic training period, after the end of the reduced training frequency period, and after the end of complete detraining: body composition, leg press 1-RM, countermovement jump, quadriceps cross-sectional area (CSA), vastus lateralis muscle architecture, and maximum aerobic power. Performance and muscle mass increased after the initial 12-week training period. Thereafter, leg press 1-RM, quadriceps CSA, and aerobic power remained unchanged in the G7 group, but decreased in G14 (-4.4 ± 3.5%; -5.9 ± 1.8%; -9.0 ± 7.8%, respectively, p < 0.05), maintaining 95.6 ± 3.5%, 94.1 ± 1.8%, and 91.0 ± 7.8% of the initial training adaptations, respectively. In conclusion, performing one training session every 2 weeks for 3 months may preserve 90 to 95% of the muscle mass/strength and aerobic power adaptations achieved with systematic concurrent training.

BACKGROUND: Compared with moderate-intensity continuous training (MICT), high-intensity interval training (HIIT) has at least a comparable effect on inhibiting an increase in fat. However, few studies have been conducted to examine the effects of detraining on body fat in rats fed a high-fat diet. The present study aimed to compare the effects of 10 weeks of HIIT or MICT as well as 6 weeks of detraining on body fat in rats fed a high-fat diet.
METHODS: After being fed a high-fat diet for 8 weeks, 54 female rats were randomly assigned to six groups: (1) CON-10, sedentary control for 10 weeks; (2) MICT-10, 10 weeks of MICT; (3) HIIT-10, 10 weeks of HIIT; (4) CON-16, sedentary control for 16 weeks; (5) MICT-16, 10 weeks of MICT followed by 6 weeks of training cessation; and (6) HIIT-16, 10 weeks of HIIT followed by 6 weeks of training cessation. The training was performed 5 days/week. The subcutaneous adipose tissue (inguinal; SCAT), visceral adipose tissue (periuterine; VAT) and serum lipid profile were analysed after 10 or 16 weeks. Adipose tissue triglyceride lipase (ATGL) protein expression in VAT was assessed by western blotting.
RESULTS: HIIT-10 and MICT-10 prevented the increase in SCAT, VAT and serum lipid levels seen in the CON group. During the 6-week detraining period, HIIT continued to prevent the increase in adipose tissue mass observed in the CON group, whereas MICT at least maintained this inhibition. The inhibition of fat mass increase was mainly the result of preventing adipocyte hypertrophy. The HIIT-10 and HIIT-16 groups showed the highest ATGL protein expression.
CONCLUSIONS: HIIT has a comparable effect to MICT on inhibiting fat accumulation in female rats; however, the inhibition of SCAT and VAT increase by HIIT is superior to MICT after short-term training cessation.

Periods of limited activity during semester break may reduce performance during return to ridden work. This study evaluated fitness and muscling of horses when returning to work, following a 12-week period during which horses either continued (conditioned) or discontinued (non-conditioned) ridden work. It was hypothesized that non-conditioned horses would have a lower level of fitness, resulting in higher resting and peak heart rates and lower levels of muscling. Twelve mature, stock type horses aged 16 ± 5 years were assigned to either a conditioned group that maintained light-to-moderate riding or a non-conditioned group receiving no formal exercise. All horses had access to voluntary exercise for 12-24hr/d on grass pasture (1.5-2.5 hectares). Following the 12-week period, all horses were placed into a light-to-moderate intensity exercise program with resting heart rate, peak heart rate, body condition score, gaskin and forearm circumference, and topline muscle measurements performed on d 0, 14, and 28. Peak and resting heart rates were not different between groups (P > 0.05) but increased for both groups throughout the study (P = 0.04). Gaskin circumference of non-conditioned horses was larger (P = 0.04), although non-conditioned horses tended to be heavier (551.4 versus 491.4 ± 21.4 kg; P = 0.07). Conditioned horses had greater average topline muscling scores (P = 0.02). Horses that were conditioned over a 12-week break had greater muscling, but changes in fitness were not detected. Pasture access could contribute to maintenance of fitness during unridden periods.

OBJECTIVE: Most athletes experience short-term training cessation because of illness, injury, post-season vacation, or other reasons. Passive muscle stiffness is a potential risk factor for a sprint-type hamstring strain injury, but limited information is available about the effect of short-term training cessation on passive muscle stiffness. The present study aimed to identify whether and how passive muscle stiffness of the biceps femoris long head (BFlh) would vary due to 2 weeks of training cessation in sprinters.
METHODS: Passive BFlh shear-wave speed (a proxy for stiffness) was measured using ultrasound shear-wave elastography in 28 male sprinters, before and after 2 weeks of intervention. During the 2 weeks, the participants in the training-cessation group (n = 14) were allowed to maintain their normal daily activities but not to perform any physical training, including stretching and resistance exercises. The participants in the training continuation group (n = 14) performed the training (including maximum speed sprint, plyometric, and weight training) prescribed by their coaches 5 days per week.
RESULTS: In the training-cessation group, passive BFlh shear-wave speed increased after the 2 weeks of training cessation (4.75 ± 0.77 to 5.00 ± 0.88 m/s, P < 0.001). In contrast, there was no significant difference before and after the 2 weeks of training continuation (4.90 ± 0.85 to 4.93 ± 0.85 m/s, P = 0.521).
CONCLUSIONS: The present findings indicate that muscles stiffen by training cessation in sprinting athletes.

This study examined the effects of exercise and detraining at a young age on fat accumulation in various organs. Four-week-old male Otsuka Long-Evans Tokushima Fatty (OLETF) rats were assigned to either the non-exercise sedentary (OLETF Sed) or exercise groups. The exercise group was subdivided into two groups: exercise between 4 and 12 weeks of age (OLETF Ex) and exercise between 4 and 6 weeks of age followed by non-exercise between 6 and 12 weeks of age (OLETF DT). Body weight was significantly lower in the OLETF Ex group than in the OLETF Sed group at 12 weeks of age. Fat accumulation in the epididymal white adipose tissue, liver, and brown adipose tissue was suppressed in the OLETF Ex group. During the exercise period, body weight and food intake in the OLETF DT group were significantly lower than those in the OLETF Sed group. However, food intake was significantly higher in the OLETF DT group than in the OLETF Sed group after exercise cessation, resulting in extreme obesity with fatty liver and brown adipose tissue whitening. Detraining after early-onset exercise promotes hyperphagia, causing extreme obesity. Overeating should be avoided during detraining periods in cases of exercise cessation at a young age.

An athlete\'s training aims to achieve the highest possible sports results by improving physical dispositions which lead to cardiac adaptive changes. The annual training cycle is divided into periods. The preparatory period begins with gradually increasing training intensity and volume until the competitive period occurs, when the athlete\'s maximum performance is expected. Finally, the athlete enters a phase of loss of fitness, which is called detraining. Detraining is a time of resting both physically and mentally from the training regime and usually lasts about 4 weeks for endurance athletes. We collected data from much research on athletes\' detraining. According to these data, the earliest change after detraining seems to be a decrease in left ventricular wall thickness and left ventricular mass, followed by decreased performance parameters, diastolic diameter of the left ventricle and size of the left atrium. A reversal of adaptive changes affects the left heart chamber first, then the right atrium and, finally, the right ventricle. Training reduction is often proposed as a method of differentiating an athlete\'s heart from cardiomyopathies. The aim of this study is to consider the diagnostic value of detraining in differentiating athletes\' hearts from cardiomyopathies. We suggest that detraining cannot be conclusive in differentiating the disease from adaptive changes. Although a withdrawal of the characteristic morphological, functional and electrocardiographic changes occurs in healthy athletes during detraining, it can also concern individuals with cardiomyopathies due to the lower expression of abnormal features after decreased training loads. Therefore, a quick diagnosis and individual assessments using imaging and genetic tests are essential to recommend a proper type of activity.

Concurrent training has been shown to be a beneficial approach to improve overall health status in older adults. However, little is known about the adaptations of this type of training in the long term (i.e., after cessation of exercise), even less in older people affected by frailty syndrome. Therefore, this study aimed (i) to assess the effects of a 6-week concurrent training program composed of power-oriented resistance training and fast walking interval training on physical function, muscle power, disability in activities of daily living and frailty in pre-frail and frail older people, and (ii) to assess the effects of a 6-month detraining period on these outcomes.
A total of 59 pre-frail and frail older adults (>75 years old; Frailty Phenotype >1) were allocated into intervention (INT; n = 32; 81.8 years; 21 women) or control (CON; n = 27; 82.5 years; 19 women) groups. Primary outcomes of this study were Short Physical Performance Battery (SPPB), relative sit-to-stand (STS) power, Barthel index, Lawton scale and Frailty Phenotype. Assessments were performed at baseline (PRE), after the concurrent training programme (POST) and after 6 months of follow-up (DET) in both groups. Mixed model repeated measures ANOVA with Bonferroni\'s post hoc tests was used.
Immediately after the intervention (∆ = POST-PRE), INT improved SPPB (∆ = 3.0 points; p < 0.001), relative STS power (∆ = 0.87 W·kg-1; p < 0.001) and reduced their frailty levels (∆ = -1.42 criteria; p < 0.001), while no changes were observed in CON. After 6 months of detraining (∆ = DET-PRE), INT showed higher SPPB (∆ = 2.2 points; p < 0.001), higher relative STS power (∆ = 0.73 W·kg-1; p < 0.001) and lower frailty (∆ = -1.24 criteria; p < 0.001) values than those reported at baseline, which were significantly different than those reported by CON. Both, Barthel index and Lawton scale values were not modified during the study in either group.
The 6-week concurrent training program improved physical function, muscle power and reduced frailty in pre-frail and frail older people and these improvements were maintained above baseline levels after 6 months of detraining. However, due to the individual variability found, future studies of long-term responders versus non-responders in frail populations are required.

This study aimed to analyze the effects of three off-season training programs on the aerobic capacity, countermovement jump (CMJ), and linear sprint performance of young male soccer players. The study employed a randomized multi-arm design, consisting of three experimental groups: i) a high-intensity interval training (HIIT) group; (ii) a plyometric jump training (PJT) group; and (iii) a HIIT+PJT group; and an inactive control group. Fifty-eight under-19 male soccer players (aged 17.6 ±0.6 years) were randomly assigned to participate in a 3-week offseason training program exclusively performing HIIT, PJT, or a combination of both, while the fourth group remained inactive. Players underwent assessments twice, using the Yo-Yo Intermittent Recovery Test - Level 1 (YYIRT), CMJ, and 30-meter linear sprint. Significant interactions between time and groups were found in CMJ (p<0.001), YYIRT (p<0.001), and 30-m sprint (p<0.001). Group*time interaction revealed that the control group was significantly different from HIIT (p<0.001), PJT (p<0.001), and HIIT+PJT (p<0.001) considering the CMJ. Moreover, the control group was significantly different from HIIT (p=0.037) in YYIRT. Finally, the control group was significantly different from HIIT (p=0.024), PJT (p<0.001), and HIIT+PJT (p=0.021) considering the 30-m sprint. In conclusion, off-season training programs are effective in significantly reducing declines in CMJ and sprint performance compared to maintaining training cessation. However, in the YYIRT, only HIIT seems to be significantly superior to maintaining inactivity. To mitigate aerobic performance declines, incorporating HIIT sessions twice weekly during the offseason is advisable. To enhance or maintain jump performance, integrating at least one session of PJT weekly is beneficial.