Three weeks of a home-based “sleep low-train low” intervention improves functional threshold power in trained cyclists: A feasibility study

Background “Sleep Low-Train Low” is a training-nutrition strategy intended to purposefully reduce muscle glycogen availability around specific exercise sessions, potentially amplifying the training stimulus via augmented cell signalling. The aim of this study was to assess the feasibility of a 3-week home-based “sleep low-train low” programme and its effects on cycling performance in trained athletes. Methods Fifty-five trained athletes (Functional Threshold Power [FTP]: 258 ± 52W) completed a home-based cycling training program consisting of evening high-intensity training (6 × 5 min at 105% FTP), followed by low-intensity training (1 hr at 75% FTP) the next morning, three times weekly for three consecutive weeks. Participant’s daily carbohydrate (CHO) intake (6 g·kg-1·d-1) was matched but timed differently to manipulate CHO availability around exercise: no CHO consumption post- HIT until post-LIT sessions [Sleep Low (SL), n = 28] or CHO consumption evenly distributed throughout the day [Control (CON), n = 27]. Sessions were monitored remotely via power data uploaded to an online training platform, with performance tests conducted pre-, post-intervention. Results LIT exercise intensity reduced by 3% across week 1, 3 and 2% in week 2 (P < 0.01) with elevated RPE in SL vs. CON (P < 0.01). SL enhanced FTP by +5.5% vs. +1.2% in CON (P < 0.01). Comparable increases in 5-min peak power output (PPO) were observed between groups (P < 0.01) with +2.3% and +2.7% in SL and CON, respectively (P = 0.77). SL 1-min PPO was unchanged (+0.8%) whilst CON improved by +3.9% (P = 0.0144). Conclusion Despite reduced relative training intensity, our data demonstrate short-term “sleep low-train low” intervention improves FTP compared with typically “normal” CHO availability during exercise. Importantly, training was completed unsupervised at home (during the COVID-19 pandemic), thus demonstrating the feasibility of completing a “sleep low-train low” protocol under non-laboratory conditions.

Does quantity matter to a stingless bee?

Quantitative information is omnipresent in the world and a wide range of species has been shown to use quantities to optimize their decisions. While most studies have focused on vertebrates, a growing body of research demonstrates that also insects such as honeybees possess basic quantitative abilities that might aid them in finding profitable flower patches. However, it remains unclear if for insects, quantity is a salient feature relative to other stimulus dimensions, or if it is only used as a “last resort” strategy in case other stimulus dimensions are inconclusive. Here, we tested the stingless bee Trigona fuscipennis, a species representative of a vastly understudied group of tropical pollinators, in a quantity discrimination task. In four experiments, we trained wild, free-flying bees on stimuli that depicted either one or four elements. Subsequently, bees were confronted with a choice between stimuli that matched the training stimulus either in terms of quantity or another stimulus dimension. We found that bees were able to discriminate between the two quantities, but performance differed depending on which quantity was rewarded. Furthermore, quantity was more salient than was shape. However, quantity did not measurably influence the bees' decisions when contrasted with color or surface area. Our results demonstrate that just as honeybees, small-brained stingless bees also possess basic quantitative abilities. Moreover, invertebrate pollinators seem to utilize quantity not only as "last resort" but as a salient stimulus dimension. Our study contributes to the growing body of knowledge on quantitative cognition in invertebrate species and adds to our understanding of the evolution of numerical cognition.

The Assessment of a Novel Lower Body Resistance Garment As a Mechanism to Increase the Training Stimulus During Running: a Randomised Cross Over Study

Background: This study examined the physiological and perceived impact of wearing a novel lower body resistance garment during exercise and recovery.Methods: Using a randomised cross over design, 15 recreationally-active males performed 2x10-minute steady-state runs followed by a 10-minute passive recovery with concomitant monitoring of oxygen consumption (V̇O2), heart rate (HR) and rating of perceived exertion (RPE; exercise portion only), wearing either the resistance garment (experimental) or running shorts (control).Results: During exercise, V̇O2 and RPE were higher (4.5% and 7.7% respectively) in experimental than control (V̇O2: r=0.24, p>0.05; RPE: r=0.32, p>0.05) whilst HR was lower (-0.4%, r=-0.05, p>0.05). During recovery, V̇O2 and HR were lower (4.7% and 4.3% respectively) in experimental than control (V̇O2: r=‑0.32, p>0.05; HR: r=-0.27, p>0.05). Conclusions: Though effects were trivial to small, and not statistically significant, these findings provide proof of concept and suggest that this garment design may increase the training stimulus during running and aid post-exercise recovery.

The Effectiveness of Small-Sided Game Practice on Improving Basic Futsal Skills

The purpose of this study was to empirically determine the provision of small-sided games 4vs2, 4vs3, and 4vs4 exercises on the basic skills of futsal athletes. This research is included in the experimental research. Participants of the study were 30 male teenage futsal athletes in Banyumas Regency. The data retrieval technique of this study used passing-controlling tests. The analysis used the normality test, homogeneity test, paired t-test test, and independent t-test with a significance level of 0.05. This study showed that the administration of SSG 4v2, 4v3, 4v4 exercises significantly influenced the fundamental skill improvement of futsal athletes. The largest increase was achieved by providing the SSG 4vs4 group with an average of ± 13.63. The results of the one-way Anova test showed that there were differences among 4vs2, 4vs3, and 4vs4 exercises. The increase might be because the SSG 4vs4 exercise suits the actual futsal game. Thus it encourages athletes to perform as many passing movements as possible. Therefore, SSG 4vs4 training is more effective in improving the basic skills of futsal athletes. It is crucial for practitioners because it allows the provision of exercises simultaneously so that training stimulus becomes more efficient.

COMPARISON OF ANTHROPOMETRIC PARAMETERS BETWEEN INDIAN ADOLESCENT MALE SWIMMERS AND NON-SWIMMERS: A CROSS-SECTIONAL STUDY

Background: During adolescence, a number of changes take place in growing children. Current study has been conducted to understand effect of sports training on the growth. Objective: The main objective of the study is to compare the anthropometric parameters in adolescent swimmers and non-swimmers. Methods: 61 boys (30 swimmers and 31non-swimmers) between age group12-17 years were selected for the study. Height, weight, biacromial breadth (BAB), bicristal breadth (BCB), mid-upper arm circumference (MUAC), waist circumference (WC), hip circumference (HC), sum of four skinfolds (SSF) namely triceps, biceps, subscapular and suprailiac, total leg length (TLL), sitting height (SH) and arm span (AS) were the anthropometric measurements taken. Independent sample t-test was used to study the difference between the two groups with p<0.05 as level of significance. Conclusion: As a response to training stimulus, the development of anthropometric parameters of swimmers are significantly different from non-swimmers. However, they follow the normal growth pattern like their non-swimming peers. <p> </p><p><strong> Article visualizations:</strong></p><p><img src="/-counters-/edu_01/0854/a.php" alt="Hit counter" /></p>

Preventive effect of sensorimotor exercise and resistance training on chemotherapy-induced peripheral neuropathy: a randomised-controlled trial

Background Chemotherapy-induced peripheral neuropathy (CIPN) is a common, unpleasant and usually long-lasting side effect of neurotoxic chemotherapeutic agents. This study aimed to investigate the preventive potential of sensorimotor- (SMT) and resistance training (RT) on CIPN. Methods Patients (N = 170) were randomised to SMT, RT or usual care (UC). Both exercise groups trained 3×/week for a total of 105 min/week during neurotoxic chemotherapy (mean length: 20 weeks). Before and 3 weeks after neurotoxic chemotherapy, CIPN signs/symptoms were assessed via Total Neuropathy Score (TNSr; primary endpoint) and EORTC QLQ-CIPN15 questionnaire. In addition, balance (centre of pressure), muscle strength (isokinetic), quality of life (QoL, EORTC QLQ-C30) and relative chemotherapy dose intensity (RDI) were investigated. The follow-up period covered 6 months after the end of chemotherapy. Results Intention-to-treat analyses (N = 159) revealed no differences regarding CIPN signs/symptoms. Exploratory per-protocol analyses (minimum training attendance rate 67%; N = 89) indicated that subjectively perceived sensory symptoms in the feet increased less during chemotherapy in the adherent exercisers (pooled group: SMT+RT) than in the UC group (−8.3 points (−16.1 to −0.4); P = 0.039, ES = 1.27). Furthermore, adherent exercisers received a higher RDI (96.6 ± 4.8 vs. 92.2 ± 9.4; P = 0.045), showed a better course of muscular strength (+20.8 Nm (11.2–30.4); P < 0.001, ES = 0.57) and QoL (+12.9 points (3.9–21.8); P = 0.005, ES = 0.64). During follow-up, CIPN signs/symptoms persisted in all groups. Conclusions This study demonstrates that SMT and/or RT alleviate subjectively perceived sensory CIPN symptoms in the feet and other clinically relevant cancer therapy-related outcomes, if an appropriate training stimulus is achieved. Clinical trial registration NCT02871284.

The effects of maturity matched and un-matched opposition on physical performance and spatial exploration behavior during youth basketball matches

The aim of this study was analyze the effect of playing against biological matched and un-matched opposition, on physical performance and spatial exploration behavior of youth basketball players. Thirty under-14 to 16 basketball players were assigned to different teams according to maturity status (Pre-, Mid-, and Post-Peak Height Velocity [PHV]), and participated in basketball matches against matched (same maturity status), and un-matched (different maturity status) opposition. Maturity status was estimated considering the percentage of predicted adult height. Workload data was collected via inertial devices (IMUs) and Ultra-Wide Band (UWB)-based system. Heart rate was recorded with individual HR monitors. The Pre-PHV performed significantly more accelerations and decelerations and explored more space against matched opposition. Against un-matched opposition, the Pre-PHV presented higher average speed, body impacts, and Player Load. Both Mid- and Post-PHV covered more distance against matched opposition than against Pre-PHV. Games against Pre-PHV involved lower distance covered, average speed, Player Load, and higher accelerations and decelerations, than against Mid- and Post-PHV. The Pre-PHV athletes performed a higher number of accelerations and decelerations comparing to the Mid and Post-PHV players. Also, a significant interaction effect (group x time) was found in distance covered, average speed, body impacts, and Player Load. The type of opposition influenced physical performance and spatial exploration behavior during basketball matches, particularly of less-mature players. Based on present findings, practitioners can select the most suitable game format, considering the physical, technical, tactical, and psychological development needs, individualizing training stimulus.

Heart Rate Variability and Physical Demands of In-Season Youth Elite Soccer Players

Monitoring fatigue and performance is important for adjusting training loads in soccer. Therefore, knowing the status of the player when applying a training stimulus is key to optimizing the players’ development. This study aims to evaluate the interaction between internal and external load, during training and matches, in an elite youth soccer team. Methods: seventeen youth players of the highest Spanish category were monitored with GPS devices during training and matches, as well as recording their nocturnal heart rate variability (HRV). We employed a linear mixed model to assess the physical demands between training and matches, and to compare the HRV variables. Results: a higher total distance (+2993.35–5746.56 m; ES = 1.4), distance at high intensity (+641.24–1907 m; ES = 1.5), sprint distance (+350.46–795.05 m; ES = 2.1), number of sprints (+18.38–41.58; ES = 1.9), and number of repeated sprints (+5.91–15.30; ES = 1.7) (all p < 0.001), but not in the number of accelerations, were reported during the matches when compared to the training sessions during the 11 weeks. The analysis of the HRV variables showed no significant differences between the accumulated values during a training week, providing similar results pre-match or post-match (p > 0.05). The LF/HFRATIO showed a negative influence on the total distance ran, distance at high intensity, distance in sprint, number of sprints, and repeated sprint. RRMEAN was positively related to the sprint number. Conclusion: the results of the present study suggest that nocturnal HRV variables are not different between pre-match and post-match. Furthermore, it suggests that LF/HFRATIO and RRMEAN during pre-match can determine the external load that the player will be able to complete during the match.

Upper-Body Resistance Training Following Soccer Match Play: Compatible, Complementary, or Contraindicated?

Purpose: During heavily congested schedules, professional soccer players can experience exacerbated fatigue responses, which are thought to contribute to an increased risk of injury. Given that match-induced residual fatigue can last up to 72 hours, many coaches naturally prioritize recovery in the days immediately following match day. While it is intuitive for coaches and training staff to decrease the amount of auxiliary training practices to focus on recovery, prescribing upper-body resistance training on the day after match play has recently emerged as a specific training modality in this context. While these sessions may be implemented to increase training stimulus, there are limited data available regarding the efficacy of such a practice to improve recovery kinetics. Methods: In this narrative review, the authors look at the theoretical implications of performing upper-body resistance training on the day after match play on the status of various physiological and psychological systems, including neuromuscular, metabolic, hormonal, perceptual, and immunological recovery. Results: The available evidence suggests that in most cases this practice, as currently implemented (ie, low volume, low intensity), is unlikely to be complementary (ie, does not accelerate recovery) but is potentially compatible (ie, does not impair recovery). Conclusion: Overall, because the perception of such sessions may be player dependent, their programming requires an individualized approach and should take into account match dynamics (eg, fixture scheduling, playing time, travel).

Stimulus Control of Odorant Concentration: Pilot Study of Generalization and Discrimination of Odor Concentration in Canines

Despite dogs’ widespread use as detection systems, little is known about how dogs generalize to variations of an odorant’s concentration. Further, it is unclear whether dogs can be trained to discriminate between similar concentration variations of an odorant. Four dogs were trained to an odorant (0.01 air dilution of isoamyl acetate) in an air-dilution olfactometer, and we assessed spontaneous generalization to a range of concentrations lower than the training stimulus (Generalization Test 1). Dogs generalized to odors within a 10-fold range of the training odorant. Next, we conducted discrimination training to suppress responses to concentrations lower than a concentration dogs showed initial responding towards in Generalization Test 1 (0.0025 air dilution). Dogs successfully discriminated between 0.0025 and 0.01, exceeding 90% accuracy. However, when a second generalization test was conducted (Generalization Test 2), responding at the 0.0025 concentration immediately recovered and was no different than in Generalization Test 1. Dogs were then tested in another generalization test (Compound Discrimination and Generalization) in which generalization probes were embedded within discrimination trials, and dogs showed suppression of responding to the 0.0025 concentration and lower concentrations in this preparation. These data suggest dogs show limited spontaneous generalization across odor concentration and that dogs can be trained to discriminate between similar concentrations of the same odorant. Stimulus control, however, may depend on the negative stimulus, suggesting olfactory concentration generalization may depend on relative stimulus control. These results highlight the importance of considering odor concentration as a dimension for generalization in canine olfactory research.