Correction: Mackala et al. Evaluation of the Pre-Planned and Non-Planed Agility Performance: Comparison between Individual and Team Sports. Int. J. Environ. Res. Public Health 2020, 17, 975.

Jozef Simenko was not included as an author in the original publication [...].

The reliability, validity and usefulness of the 30-15 intermittent fitness test for cardiorespiratory fitness assessment in military personnel.

The objectives of this study were to investigate the reliability, validity, and usefulness of the 30-15 intermittent fitness test (30-15IFT) in soldiers. The 34 infantry members of the Slovenian armed forces were recruited as participants. Participants performed the continuous incremental treadmill test (TR), a 2-mile run (2MR) test, and two 30-15IFT tests. Additionally, participants were divided into a highest-scoring group (HSG) and a lowest-scoring group (LSG) based on their scores on the Army Physical Fitness Test. A very high reliability ratings were observed for 30-15IFT measures, as follows: end-running speed (ERS) ERSIFT (ICC = 0.971), maximal heart rate (HRmax) HRmaxIFT (IC = 0.960), and maximal relative oxygen consumption (VO2max) VO2max-IFT (ICC = 0.975). Although 30-15IFT measures demonstrated high correlations (r = 0.695-0.930) to the same measures of TR test, ERS, HRmax and VO2max were higher in the 30-15IFT (p > 0.05). Furthermore, ERSIFT and predicted VO2maxIFT were higher in HSG compared to LSG, whereas HRmax did not differ. The results of this study show that the 30-15IFT test is a reliable, valid and useful tool for assessing cardiorespiratory fitness in the armed forces. Moreover, the ERS and predicted VO2max values derived from the 30-15IFT could be considered more sensitive markers of combat readiness than the parameters derived from the TR and 2MR tests.Trial registration number: NCT05218798.

Reliability and validity of 30-15 intermittent fitness test for cardiorespiratory fitness assessment among infantry members of Slovenian armed forces: A study protocol.

Introduction: Cardiorespiratory fitness (CRF) testing is routinely performed by most armed and tactical forces around the world as part of their recruitment process for new members or simply as an annual examination of their personnel. A 2-mile run (2MR) test is among the most commonly used. However, as it is performed outdoors, weather, climate, and terrain can influence the results and often limit the maximum performance. Also, this test has been shown to be difficult for individuals because the pacing strategy is self-paced. As such, it does not reflect the real situation on the battlefield, where most activities are externally driven by the environment and the enemy. Therefore, we believe that the 30-15 Intermittent Fitness Test (30-15IFT) may be a suitable tool for measuring CRF and battle readiness of military personnel. Moreover, given the importance of visual attention to military personnel we aim to investigate the differences in visual attention between better and less physically prepared infantry members and its corresponding response to maximal endurance running test. Methods and analysis: This randomized cross-over study using a within-subjects test-retest design will enroll 32 infantry members of the Slovenian Armed Forces. To investigate the reliability and validity of the 30-15IFT test, an incremental treadmill test (TR), a 2MR test, and two identical 30-15IFT will be performed in randomized order. Additionally, participants will be subsequently divided into two groups based on their score on the Army Physical Fitness Test (APFT), whereas differences in visual attention will be assessed by using the d2 test. The primary analysis will assess differences in key physiological outcomes between the different CRF tests (TR vs. 2MR vs. 30-15IFT). In addition, the relative reliability of all dependent variables between two 30-15IFT trials will be estimated by interclass correlation coefficient (ICC), while relationship between maximal oxygen uptake, heart rate and maximal running speed of 30-15IFT, TR and 2MR will be assessed using Pearson's correlation. Ethics and dissemination: Ethical approval was obtained from the National Medical Ethics Committee (reference number: 0120-495/2021/6). The results of the proposed study will be disseminated through publication in peer-reviewed journals. Clinical Trial Registration: [www.ClinicalTrials.gov], identifier [NCT05218798].

Reducing energy availability in male endurance athletes: a randomized trial with a three-step energy reduction.

Background: Low energy availability (EA) can be detrimental for athlete health. Currently, it is not known what the threshold for low EA in men is, and what effects it may have on performance. Methods: This study was set to determine potential effects of low EA by modulating male participants' exercise energy expenditure and controlling energy intake and consequently manipulating EA in three progressive stages (reducing EA by 25%%, and 75 %). Performance was measured with three specific tests for explosive power, endurance, and agility. Blood was drawn, resting energy expenditure was monitored and two questionnaires were repetitively used to address any changes in eating behaviors and well-being. Results: Repeated measured design showed poorer performance (power output 391.82 ± 29.60 vs. 402.5 ± 40.03 W, p = 0.001; relative power output 5.53 ± 0.47 vs. 5.60 ± 0.47 W/kg, p = 0.018; explosive power 0.28 ± 0.04 vs. 0.32 ± 0.05 m, p = 0.0001, lactate concentration 7.59 ± 2.29 vs 10.80 ± 2.46 mmol/L, p = 0.001). the quartile range for testosterone was lower (2.33 ± 1.08 vs. 2.67 ± 0.78, p = 0.026) and there was a tendency for lower triiodothyronine (4.15 ± 0.61 vs. 4.46 ± 0.54 pmol/L, p = 0.072). Eating behaviors and well-being were worse (46.64 ± 7.55 vs. 24.58 ± 7.13, p = 0.011 and 15.18 ± 2.44 vs. 17.83 ± 3.54, p = 0.002). The intervention also resulted in lower body fat (8.44 ± 3.15 vs. 10.2 ± 2.5%, p = 0.013). Conclusions: Analysis showed that most of the negative effects occurred in the range of 9-25 kCal·kg∙FFM·d-1. This is the range where we suggest a threshold for LEA in men could be. Reducing EA impaired explosive power first, then endurance. It was associated with a reduction in testosterone, triiodothyronine and there was a tendency for reduced IGF-1, but hormones were more resilient to changes in EA. Psychological assessment of eating behaviors and well-being proved to be very useful, whereas monitoring resting energy expenditure did not.

Inducing low energy availability in trained endurance male athletes results in poorer explosive power.

PURPOSE: Low energy availability in males needs more original research to understand its health and performance consequences. The aim of the study was to induce low energy availability in previously healthy male endurance athletes by reducing energy availability by 25% for 14 consecutive days and measure any potential changes in performance, health, mental state or energy markers. METHODS: Energy availability was reduced in 12 trained, well-trained and elite endurance athletes by increasing energy expenditure and controlling energy intake. After intervention, health was assessed by blood draw, body composition was measured, energy markers by measuring resting energy expenditure, performance with three specific tests (measuring endurance, agility and explosive power) and two questionnaires were used for psychological assessment (the Three Factor Eating Questionnaire and Well-being questionnaire). RESULTS: Reduced energy availability (22.4 ± 6.3 kcal/kg FFM/day) caused significantly lower haemoglobin values (t(12) = 2.652, p = 0.022), there was a tendency for lower iron and IGF-1 (p = 0.066 and p = 0.077, respectively). Explosive power was reduced (t(12) = 4.570, p = 0.001), lactate metabolism was altered and athletes reported poorer well-being (t(12) = 2.385, p = 0.036). Cognitive restriction was correlated with energy availability (r = 0.528, p = 0.039). CONCLUSION: This is the first research providing direct evidence that suboptimal energy availability negatively impacts explosive power before hormonal changes occur in male endurance athletes. It is also the first to show direct association of low energy availability and higher cognitive restriction. We also observed worse well-being and lower haemoglobin values. 25% of energy availability reduction as not enough to elicit changes in resting energy expenditure.

Morphological Asymmetries Profile and the Difference between Low- and High-Performing Road Cyclists Using 3D Scanning.

The aims of this study are: (1) to identify morphological asymmetries in road cycling by using a novel 3D scanning method and electrical bioimpedance, (2) to investigate possible asymmetries in road cyclists of low (LPG) and high (HPG) performance group, (3) to compare the number of morphological asymmetries between HPG and LPG of cyclists, and (4) to explore correlations between asymmetry scores and competition performance. Body composition and 3D anthropometric measurements were conducted on 48 top-level male road cyclists (178.98 ± 5.39 cm; 68.37 ± 5.31 kg) divided into high (n = 22) and low (n = 26) performance groups. Competition performance (CP) is represented through racing points gathered at the end of the competition season. The latter was used to divide road cyclists into low- and high-performing groups. One-way ANOVA was used to determine differences between groups, while paired-samples T-test and Absolute Asymmetry index (AA) were calculated (p ≤ 0.05) for paired variables inside the groups, and the Spearman correlation coefficient was used to explore correlations between AA and CP. Results showed statistically significant differences between the left and right side of different body segments (16 paired variables) among low-performing road cyclists in five paired variables of the upper body: elbow girth (4.35, p = 0.000), forearm girth (6.31, p = 0.000), arm surface area (2.54, p = 0.018), and arm volume (2.71, p = 0.012); and six paired variables of the lower body: leg lean mass (5.85, p = 0.000), leg length (3.04, p = 0.005), knee girth (4.93, p = 0.000), calf girth (5.25, p = 0.000), leg surface area (4.03, p = 0.000), and leg volume (5.3, p = 0.000). Altogether, the high-performing group of road cyclists statistically differed only in 2 out of 16 paired variables of the upper body: elbow girth (4.93, p = 0.000) and in forearm girth (5.12, p = 0.000). Low- and high-performing groups were statistically significantly different in the asymmetry of leg lean mass F(1,46) = 6.25, p = 0.016 and asymmetry of the calf girth F(1,46) = 7.44, p = 0.009. AA of calf girth on the total sample (n = 48) showed a significant correlation with CP (r = -0.461; p = 0.001). In conclusion, the study's main finding was that high-performance road cyclists are more symmetrical than the low-performance group, for which it is significant to have a higher amount of morphological asymmetries.

Multidimensional prediction approach in the assessment of male volleyball players' optimal body composition: the case of two elite European teams / Enfoque de predicción multidimensional en la evaluación de la composición corporal óptima de los jugadores de voleibol masculino: el caso de dos equipos europeos de élite

SUMMARY: This research aimed to create a multidimensional equation for predicting an optimal body composition model for elite-level European male volleyball players. The subject sample consisted of 36 elite volleyball players: national team members from two European countries - Slovenia and Serbia - in the 2017 season. Measurement of body composition was carried out using electrical multichannel bioimpedance (BIA - InBody 720), in which 11 variables were used (body height as a longitudinal one, and the other 10 as a system of body composition indicators). Based on the results of descriptive statistics, we can state that elite European male volleyball players are tall, heavy, and with nutritional status at the level of 198.5?6.5 cm, 92.3?5.9 kg and 23.44?1.44 kg•m-2, respectively. The percentage of body fat in the whole sample was 7.91?3.03 %, and the skeletal muscle mass index averaged 12.49?0.80 kg•m-2. For the evaluation and prediction of an optimal body composition model of elite male volleyball players, a multidimensional score (BC_Score) was defined, based on a simple, but sport-specific and playing position-sensitive model equation based on three dominant body characteristics of elite volleyball players: BH, PBF, and SMMI. In this manner, coaches can have a tool for managing the body composition status of players according to position, in terms of a deterministic, fully controlled system.

RESUMEN: Esta investigación tuvo como objetivo crear una ecuación multidimensional para predecir un modelo de composición corporal óptimo para los jugadores de voleibol masculinos europeos de élite. La muestra consistió en 36 jugadores de voleibol de élite, miembros del equipo nacional de dos países, Eslovenia y Serbia, en la temporada 2017. La composición corporal se realizó mediante bioimpedancia eléctrica multicanal (BIA - InBody 720), en la que se utilizaron 11 variables (la altura corporal como longitudinal y las otras 10 como sistema de indicadores de composición corporal). Con base en los resultados de las estadísticas descriptivas, observamos que los jugadores de voleibol de élite europeos son altos, pesados y con un estado nutricional de 198,5 ? 6,5 cm, 92,3 ? 5,9 kg y 23,44 ? 1,44 kg•m-2, respectivamente. El porcentaje de grasa corporal en toda la muestra fue de 7,91 ? 3,03 % y el índice de masa del músculo esquelético promedió 12,49 ? 0,80 kg•m-2. Para la evaluación y predicción de un modelo de composición corporal óptimo de jugadores de voleibol masculino de élite, se definió una puntuación multidimensional (BC_Score), basada en una ecuación de modelo simple, pero específica del deporte y sensible a la posición de juego, basada en tres características corporales dominantes de la élite. Jugadores de voleibol: BH, PBF y SMMI. De esta manera, los entrenadores pueden disponer de una herramienta para gestionar el estado de la composición corporal de los jugadores según la posición, en términos de un sistema determinista y totalmente controlado.

Relationship between energy availability, energy conservation and cognitive restraint with performance measures in male endurance athletes.

BACKGROUND: Low energy availability in male athletes has gained a lot of attention in recent years, but direct evidence of its effects on health and performance is lacking. The aim of this research was to objectively measure energy availability (EA) in healthy male endurance athletes without pre-existing relative energy deficiency signs during pre-race season. METHODS: Twelve trained endurance athletes (performance level 3, 4, and 5) participated in the cross-sectional controlled laboratory study. Fat-free mass, exercise energy expenditure, and energy intake were measured to calculate EA. Resting energy expenditure was measured and estimated to assess energy conservation. Three specific performance tests were used to assess endurance, agility, and explosive strength performance. For psychological evaluation, the Three Factor Eating Questionnaire and a short Well-being questionnaire were completed. RESULTS: Mean EA was 29.5 kcal/kg FFM/day. The majority (66.6%) had EA under the threshold for low EA in females. Critical cognitive restraint (≥13) was reported by 75% of participants. There were no differences in performance, blood values, or psychological evaluation when subjects were divided into two groups divided by EA = 30 kcal/kg FFM/day. Cognitive restraint was negatively associated with measured resting energy expenditure and energy conservation (r = -.578, p = .025 and r = -.549, p = .032, respectively). CONCLUSIONS: The mean EA measured in this study supports the theory that the threshold for low EA in endurance male athletes might be under the threshold for females. In addition, we confirmed cognitive restraint could be useful for early detection of energy conservation. The high cognitive restraint as measured in our sample stressed the need of eating behavior screening in endurance athletes in order to reduce risk of any disordered eating patterns.

The Effect of Height on Drop Jumps in Relation to Somatic Parameters and Landing Kinetics.

The aim of this study was to assess the effect of drop height and selected somatic parameters on the landing kinetics of rebound jumps in force and power production, performed by male and female student athletes. Twenty female and forty male students with a sports background participated in the experiment (mean and standard deviation (± SD): age 20.28 ± 1.31 years, height 166.78 ± 5.29 cm, mass 62.23 ± 7.21 kg and 21.18 ± 1.29, 182.18 ± 6.43, 78.65 ± 7.09). Each participant performed three maximal jumps on two independent and synchronized force platforms (Bilateral Tensiometric Platform S2P) at each of the two assigned drop-jump heights (20-, and 40-, cm for female and 30-, and 60-, cm for the male special platform). Significant between-sex differences were observed in all variables of selected somatics, with men outperforming women. Statistically significant differences were noted in four parameters, between men and women, in both DJs from 20/40 and 30/60 cm. The height of the jump was 6 cm and 4 cm higher for men. A slightly higher statistical significance (p = 0.011) was demonstrated by the relative strength (% BW) generated by the left limb in both men and women. Only women showed a significant relationship between body mass, body height, and five parameters, dropping off of a 20 cm box. In men, only the left leg-relative maximal F (p =-0.45)-showed a relationship with body mass. There were no relationships between the above-mentioned dependencies in both groups, in jumps from a higher height: 40 cm and 60 cm. From a practical application, the DJ with lower 20/30 cm or higher 40/60 cm (women/men) respectively emphasizes either the force or power output via an increase in the velocity component of the rebound action or increased height of the DJ jump.

Evaluation of the Pre-Planned and Non-Planed Agility Performance: Comparison between Individual and Team Sports.

This study assessed differences in agility performance between athletes of team and individual sports by assessing change-of-direction speed (CODS) as pre-planned agility and reactive agility (RA) as non-planed in different spatial configurations. The study involved 36 individual (sprint, hurdles, jumping, tennis, and judo) and 34 team (soccer, basketball, and handball) athletes. CODS and RA were measured with a light-based reactive training system in a frontal (FR), universal (UN), semicircular (SC), and lateral (LA) design. Lower limb power and sprint performance were also measured in a 10 m single leg jump test and 15 m sprint. Individual athletes showed significantly better performance in three of the eight agility tests: LA-RA, UN-RA, and SC-CODS (p < 0.008, p < 0.036, and p < 0.027, respectively) and were found to present stronger correlations (p < 0.01) between jump test performance and the CODS condition. Team athletes showed stronger associations between sprint performance and the CODS condition. In the RA condition both jump and sprint performance showed stronger correlations in the group of individual athletes. Agility performance as measured by CODS and RA should improve with enhanced of motor proficiency. Finally, the tests applied in this experiment seem to be multidimensional, but require spatio-temporal adjustment for their implementation, so that they meet the requirements of the particular sport.

Are Change-of-Direction Speed and Reactive Agility Independent Skills Even When Using the Same Movement Pattern?

Coh, M, Vodicar, J, Zvan, M, Simenko, J, Stodolka, J, Rauter, S, and Mackala, K. Are change-of-direction speed and reactive agility independent skills even when using the same movement pattern? J Strength Cond Res 32(7): 1929-1936, 2018-The purpose of this investigation was to determine whether there are differences between the 2 approaches to quantifying agility (preplanned vs. unplanned response) when reacting to a stimulus in an identical spatial scenarios. The study involved 45 male and 31 female trained athletes (age 21.2 ± 1.78 and 20.6 ± 1.27 years, body height 181.6 ± 8.31 and 167.7 ± 5.03 cm, and body mass 78.9 ± 11.33 and 63.3 ± 8.65 kg, respectively). A light-based reactive training system was used to measure the time to completion in a task that assessed agility by change-of-direction speed (CODS) in a preplanned condition and reactive agility (RA) in an unplanned condition across 4 spatial configurations. Sprint performance in a 30-m sprint and lower limb reactive power in a 10-m single leg jump test was also measured. Significant differences (p ≤ 0.05) were found between men and women in all tests and between performance in the CODS and RA condition for each spatial configuration. Significant correlations were observed between 30-m starting sprint speed and CODS and RA performance measured in a semicircle (r = 0.62, r = 0.60) and lateral (r = 0.54, r = 0.58) configuration in male athletes. The present findings suggest that CODS and RA are 2 different and independent skill domains that define agility. These qualities should be diagnosed by discrete assessments and enhanced by different training methodologies.

Body asymmetries in young male road cyclists / Asimetrías corporales en ciclistas de carretera masculinos jóvenes

An anthropometric analysis was conducted on 64 competitive young male road cyclists of different age categories (U17; U19; & U23 years of age). The purpose of the study is to find asymmetries between the left and right side of upper and lower limbs with the NX-16 (TC2) 3D body scanner, which includes measurement of left and right upper arm girth, elbow girth, forearm girth, wrist girth, thigh girth, knee girth, thigh length, calf girth, and shin length. Body composition was measured by the bioelectrical impedance machine InBody 720 (Biospace Ltd.). Results of body composition measurements of male road cyclists showed that U17 and U19 youth road cyclist differed statistically in five (from 11) paired variables, and the U23 age group differed statistically in six (from 11) paired variables. All of the age groups differed statistically in elbow, forearm, and calf girth. The main finding of study was that as the age of a cyclist increases, there is a tendency to increase asymmetries between the left and right side of several body segments.

Se realizó un análisis antropométrico de 64 ciclistas hombres, competidores de carretera, de diferentes categorías de edad (M17 y M23 años). El objetivo del estudio fue encontrar asimetrías entre el lado izquierdo y el lado derecho de los miembros superiores e inferiores con escáner corporal NX-16 (TC2) 3D, que incluyó la medición de las circunferencias izquierda y derecha de la parte superior del brazo, circunferencia del codo, circunferencia del antebrazo, y de la muñeca, circunferencia del muslo, de la cintura y de la rodilla; se midió el largo del muslo, circunferencia de la pantorrilla y el largo de la tibia. La composición corporal se midió mediante la máquina de impedancia bioeléctrica InBody 720 (Biospace Ltd.). Los resultados de las mediciones de la composición corporal de los ciclistas de carretera mostraron que los ciclistas juveniles de las categorías M17 y M19 difirían estadísticamente en cinco (de 11) variables pareadas, y el grupo de edad de los 23 años difirió estadísticamente en seis variables. Todos los grupos etarios difirieron estadísticamente en el codo, el antebrazo y en la circunferencia de la pantorrilla. El principal hallazgo del estudio indicó que al aumentar de edad un ciclista, se observa un aumento de la asimetría entre los lados izquierdo y derecho de varios segmentos corporales.

Runners as sport tourists: the experience and travel behaviors of Ljubljana Marathon participants.

The study analysed the experiences of participants on mass sport events, and explained the influence of such sport events on the lifestyle of runners. The study sample consisted of 664 participants of the 15th Ljubljana Marathon. The TRPS questionnaire was adjusted to establish the tourist roles. The role of sport tourists was assumed by 29.8% of all participants. Sport tourists who take various trips mainly for sport purposes (66.7%) participate more often in mass sport events at home and abroad and are more physically active in their leisure time. Moreover, 13 in-depth interviews were conducted with selected marathon participants. It was established that different travel behaviour and experiences from earlier sport events have influenced on their lifestyles.