Nutrition practices of Lithuanian elite international and national-level male bodybuilders in the pre-competition period

OBJECTIVES: To compare the pre-competition nutrition practices of Lithuanian elite international-level (IL) and national-level (NL) bodybuilders. METHODS: Sixteen male bodybuilders (n=8 per group) were enrolled. The IL group comprised individuals achieving 1st to 4th place in the World and European Championships organized by the IFBB, whereas the NL group ranked between 1st and 6th place in the national championships. Body mass and diet data were obtained via a questionnaire. A repeated-measures ANOVA was performed using time as a within factor and group as a between factor. RESULTS: Both groups experienced a reduction in body mass during the pre-competition phase (p<0.001), which was slower in the IL than in the NL group (p=0.048). Both groups exhibited a reduction in caloric (p<0.001), carbohydrate (p<0.001), and fat (p=0.006) intake relative to body mass, but not in protein intake. Nevertheless, the IL group had a higher intake of calories (p=0.015), protein (p<0.001), but not carbohydrates relative to body mass vs. the NL group. CONCLUSIONS: The Lithuanian IL and NL bodybuilders both reduced calories by cutting fat and carbohydrates during pre-competition. The IL group maintained higher calorie and protein intake, resulting in similar body mass loss but at a slower rate than the NL group

Effect of low vs. high carbohydrate intake after glycogen depleting workout on subsequent 1500 m run performance in high-level runners

Carbohydrate (CHO) metabolism is crucial for short-duration, high-intensity exercise performance, but the effects of variations in glycogen availability have not been investigated in field trials of trained athletes. This study was designed to test how 1500 m time trial (TT) performance is affected by the manipulation of pre-race glycogen reserves. Competitive middle-distance runners (n = 11 (4 females)) completed a 1500 m individually paced indoor TT after abundant (high, >5 g/kg/d) or restricted (low, <1.5 g/kg/d) dietary CHO intake for 2 days after a glycogen-depleting session. Stride pattern, heart rate (HR), capillary blood lactate, and glucose and plasma malondialdehyde (MDA) response were determined. The TT was slower in low vs. high condition by 4.5 (4.5) s (~2%; p < 0.01), with a tendency toward shorter stride length. Blood lactate and glucose were lower before the TT in low vs. high condition (1.8 (0.5) vs. 2.2 (0.7) mmol/L and 5.4 (0.7) vs. 5.9 (0.8) mmol/L, p = 0.022 and 0.007, respectively), and peak lactate was higher in high vs. low condition (16.8 (3.1) vs. 14.5 (4.2) mmol/L, p = 0.039). Plasma MDA was the same before the TT, and 15 min after the TT, it increased similarly by 15% in low (p = 0.032) and high (p = 0.005) conditions. The restriction of pre-test CHO intake impaired 1500 m TT performance and reduced baseline and peak blood lactate concentrations but not blood glucose or MDA response.Peer reviewe

Effect of Lower Body Compression Garments on Hemodynamics in Response to Running Session

Purpose. Compression garments are often worn during exercise and allegedly have ergogenic and/or physiological effects. In this study, we compared hemodynamics and running performance while wearing compression and loose-fit breeches. We hypothesized that in neutral-warm environment compression breeches impair performance by diminishing body cooling via evaporative sweat loss and redistributing blood from active musculature to skin leading to a larger rise in body temperature and prolonging recovery of hemodynamics after exercise. Methods. Changes in hemodynamics (leg blood flow, heart rate, and blood pressure during orthoclinostatic test), calf muscle tissue oxygenation, and skin and core temperatures were measured in response to 30 min running (simulation of aerobic training session) followed by maximal 400 m sprint (evaluation of running performance) in recreationally active females (25.1±4.2 yrs; 63.0±8.6 kg) wearing compression or loose-fit breeches in randomized fashion. Results. Wearing compression breeches resulted in larger skin temperature rise under the garment during exercise and recovery (by about 1°C, P<0.05; statistical power > 85%), while core temperature dynamics and other measured parameters including circulation, running performance, and sensations were similar compared to wearing loose-fit breeches (P>0.05). Conclusion. Compared with loose-fit breeches, compression breeches have neither positive nor negative physiological and performance effects for females running in thermoneutral environment

COMPARISON OF PHYSIOLOGICAL, PHYSICAL AND PSYCHOLOGICAL DEMANDS OF 3X3 BASKETBALL AND HIIT IN SEDENTARY FEMALE ADULTS

Sedentary behavior (SB) which is defined as the lowest level of physical activity has recently become a topic of increased research interest in the fields of physical, physiological and psychological aspects due to its effect on human wellness. High- Intensity Interval Training (HIIT) is one of the training methods that has been used for sedentary people due to its short duration. However, according to previous research, between 30 and 50 percent of sedentary people quit exercising (Antoniewicz and Brand et al., 2016). Therefore, there is a need for appropriate physical exercise for adults to encourage their participation and to have a positive impact on their overall health. In this regard, team sports activities have been proposed as an alternative way to HIIT for people due to their contribution to health- related aspects (Conte, D. et al., 2023; Castagna C et al., 2018). However, there is no research on basketball games’ impact on sedentary female adults. Therefore, the aim of the present study was assessing and comparing the physiological [(percentage of maximal heart rate (%HRmax), blood lactate (BLa), creatine kinase (CK)], enjoyment, [rating of perceived exertion (RPE)] and physical [percentage of moderate-to-vigorous physical activity (%MVPA) and vigorous activity (%VA)] responses to recreational 3×3 basketball (3x3BB) and high-intensity interval training (HIIT) in sedentary female adults. Twelve apparently healthy, adult sedentary women, (age: 37 ± 14 y; body mass: 66 ± 19kg; stature: 162 ± 13 cm; fat mass: 27.5 ± 12.5 %) executed a 3x3BB match and HIIT with comparable duration. While BLa was assessed both before and after each session,%HRmax,%MVPA, and%VA were measured during the protocols. RPE and enjoyment were evaluated at the conclusion of each experiment, whereas CK was measured prior to protocols and after 48 hours. 3x3BB elicited higher%HRmax (p&lt;0.001; d= –1.64, Large),%MVPA (p&lt;0.001; d=7.17, Very Large),%VA (p=0.001; d=2.91, very large), while no difference was found in enjoyment (p=0.233; r –  value= 0.250, small), and RPE (p=1; r value = –0.000, no effect) compared to HIIT condition. In addition, greater BLa values were observed in the HIIT post-condition when compared to the 3x3BB post-condition (p=0.018; r-value= –0.624, Large) (P value adjusted by Bonferroni), whereas CK analysis revealed no significant difference in general (p=0.216; r-value= –0.449, Medium) (P value adjusted by Bonferroni). In comparison to HIIT, 3x3BB causes greater%HRmax, physical activity intensities, similar enjoyment, RPE, CK and lower BLa in sedentary female adults, suggesting that it may be a beneficial activity to improve participants’ health.Keywords: sedentary behavior, 3x3 basketball, High-intensity interval training

High-velocity elastic-band training improves hamstring muscle activation and strength in basketball players.

BACKGROUND:The aim of this study was use surface EMG activity to assess changes in co- activation of knee flexors and extensors muscle groups during elastic-band exercise after 5 weeks of high-velocity elastic-band training in basketball players. METHODS:College male basketball players (n = 18) were randomly divided into one of two groups: (1) The elastic-band training group performed low-load and high-velocity - lying prone - hamstring curls training three times per week; (2) The control group did not do any training. Pre- and post- training assessment included concentric knee extension and flexion at 60°/s and 240°/s, and the frequency of knee flexion and extension with elastic bands in the prone position. The EMG of the rectus femoris, semitendinosus muscles and the long head of the biceps femoris were assessed during these activities, and 30-m sprint running speed was measured from a stationary start and a running start. RESULTS:It was shown that high-velocity elastic-band training was 1) feasible, 2) increased movement velocity and 3) muscle strength, 4) altered neural control such that excessive lengthening of the hamstring muscle, and hence strain-injuries, may be prevented and 5) improved sprint performance in basketball players. CONCLUSIONS:In addition, these results suggest that high-velocity elastic-band training may be a tool to prevent hamstring strain-injuries in basketball players

Human alpha-actinin-3 genotype association with exercise-induced muscle damage and the repeated-bout effect

Alpha-actinin-3 (ACTN3) is an integral part of the Z line of the sarcomere. The ACTN3 R577X (rs1815739) polymorphism determines the presence or absence of functional ACTN3, which may influence the extent of exercise-induced muscle damage. This study aimed to compare the impact of, and recovery from, muscle-damaging eccentric exercise on subjects with or without functional ACTN3. Seventeen young men (20-33 years old), homozygous for the R (n = 9) or X (n = 8) alleles, performed two bouts of stretch-shortening exercise (50 drop jumps) two weeks apart. Muscle soreness, plasma creatine kinase (CK) activity, jump height, maximal voluntary isometric torque (MVC), peak concentric isokinetic torque (IT), and electrically stimulated knee extension torques at 20 and 100 Hz were measured at baseline and at a number of time points up to 14 days after each bout. There were no significant baseline differences between the groups. However, significant time point &times; genotype interactions were observed for MVC (p = 0.021) and IT (p = 0.011) for the immediate effect of eccentric exercise in bout 1. The RR group showed greater voluntary force decrements (RR vs. XX: MVC, -33.3% vs. -24.5%; IT, -35.9% vs. -23.2%) and slower recovery. A repeated-bout effect was clearly observed, but there were no differences by genotype group. The ACTN3 genotype modulates the response of muscle function to plyometric jumping exercise, although the differences are modest. The ACTN3 genotype does not influence the clearly observed repeated-bout effect; however, XX homozygotes recover baseline voluntary torque values faster and thus may be able to undertake more frequent training sessions

Effect of Whole-body Vibration frequency on muscle tensile state during graded plantar flexor isometric contractions

Acute physiological and biomechanical alterations have been reported following whole-body vibration (WBV). Stiffening of muscles has only been anecdotally reported in response to WBV. Accordingly, this study investigated active plantar flexor muscle stiffness in response to a single WBV bout at four mechanical vibration frequencies

The effects of high-velocity hamstring muscle training on injury prevention in football players

Background: Explosive and fast body movements, sprints, jumps and quick changes of direction, which are characteristic of the football training, place considerable strain on the hamstring muscles. Due to the high occurrence of hamstring injuries, new preventive strategies are required that focus on high-velocity training. The purpose was to assess the effectiveness of high-velocity elastic-band training in reducing the occurrence of hamstring injuries in football players.Methods: Male football players from 15 teams (n = 319) playing in national competitions participated in this study. The players were involved in a 5-week exercise period in either the intervention group (INT) or the control group (CON), with a follow-up period of ∼4 months where hamstring injuries and exposure time were recorded. The INT group had two to three sessions per week of elastic-band training with low-load, high-velocity leg curls while lying prone; the CON group performed self-paced football-specific drills.Results: The incidence rate of hamstring injuries was 6.5% in the INT group (8 out of 123 players) and 9.2% in the CON group (18 out of 196 players). Although the INT group showed almost 1/3 reduction in hamstring injury incidence compared to the CON group, the difference was not statistically significant (p &gt; 0.05). Moreover, no differences (p &gt; 0.05, odds ratio [OR] = trivial-to-small) in distribution between the groups were found in hamstring injury characteristics (leg dominance and mechanism) except for the distribution of injuries that occurred during matches or training (p = 0.036; OR = 6.14, moderate).Conclusion: The program of high-velocity elastic-band training did not prove to be effective in preventing hamstring muscle injuries in football players despite displaying some positive indications that could be considering when creating injury prevention programs

Prefrontal Cortex Activity Predicts Mental Fatigue in Young and Elderly Men During a 2 h “Go/NoGo” Task

Background: Although the effects of mental fatigue on cognitive–motor function and psychological state in young adults are well-documented, its effects in the elderly are not completely understood. The aim of this study was to estimate the effect of prolonged cognitive load on the indicators of psychological, cognitive, and motor functions.Methods: Fifteen young and 15 elderly men were asked to perform a 2 h “Go/NoGo” task. Psychological state (mood and motivation), cognitive (prefrontal cortex activity and cognitive performance), and motor (motor cortex excitability and grip strength) functions were measured before and after the task. During the 2 h task, both groups had a significantly similar increase in the number of “Incorrect NoGo” errors. Only in young men reaction time (RT) of “Incorrect NoGo” and intraindividual variability of RT of “Incorrect NoGo” significantly increased during task. After the task, handgrip strength decreased for the young men, whereas latency of motor evoked potentials prolonged both groups. Nevertheless, both groups indicated that they felt fatigue after the 2 h task; we observed that mental demand increased, whereas intrinsic motivation and mood decreased only in young men. Prolonged task decreased the switching/rest ratio of oxygenated hemoglobin for the young and the elderly men; however, greater for elderly than young men. Interestingly, the more the prefrontal cortex was activated before the 2 h task during the switching task, the fewer of “Incorrect NoGo” errors made by the young men and the greater the number of errors made by the elderly men.Conclusion: Because of the greater mental load and (possibly) greater activation of prefrontal cortex during the 2 h “Go/NoGo” task, there was greater mental and neuromuscular performance fatigue in young men than in elderly men

Skeletal muscle PGC-1α1 reroutes kynurenine metabolism to increase energy efficiency and fatigue-resistance

The coactivator PGC-1α1 is activated by exercise training in skeletal muscle and promotes fatigue-resistance. In exercised muscle, PGC-1α1 enhances the expression of kynurenine aminotransferases (Kats), which convert kynurenine into kynurenic acid. This reduces kynurenine-associated neurotoxicity and generates glutamate as a byproduct. Here, we show that PGC-1α1 elevates aspartate and glutamate levels and increases the expression of glycolysis and malate-aspartate shuttle (MAS) genes. These interconnected processes improve energy utilization and transfer fuel-derived electrons to mitochondrial respiration. This PGC-1α1-dependent mechanism allows trained muscle to use kynurenine metabolism to increase the bioenergetic efficiency of glucose oxidation. Kat inhibition with carbidopa impairs aspartate biosynthesis, mitochondrial respiration, and reduces exercise performance and muscle force in mice. Our findings show that PGC-1α1 activates the MAS in skeletal muscle, supported by kynurenine catabolism, as part of the adaptations to endurance exercise. This crosstalk between kynurenine metabolism and the MAS may have important physiological and clinical implications