Kinematic characteristics of elbow joint range of motion in elite Chinese freestyle swimmers with elbow pain during dry-land simulations of swimming strokes.

The aim of this study was to obtain quantitative data on elbow joint ROM in elite freestyle swimmers with EP in China. Of the 50 elite freestyle swimmers recruited, 41 completed all measurements during dry-land swimming stroke simulations. Elbow joint angle, velocity, and acceleration were measured using inertial measurement units. The RMSE/D was calculated to determine the elbow joint ROM deviation. Joint angle (3.33 ∘-42.96 ∘), angular velocity (-364.15 to 245.69 ∘/s), and angular acceleration (-7051.80 to 1465.35 ∘/s2) were significantly different between the critical pain and healthy. The probability distributions of joint angle (15.47 ∘ ±14.54 ∘), angular velocity (2.41 ∘ ±111.06 ∘/s), and angular acceleration (1.93 ± 2222.6 ∘/s2) in the slight pain group were significantly different betweenhealthy and critical pain. The RMSE/D distributions of angular velocity (28.3%) and acceleration (21.48%) in the critical pain deviated from the healthy. The peak value-RMSE/D matrix model obtained proved that elbow ROM significantly differed between the elite freestyle swimmers with EP and the healthy. Angular velocity and acceleration indicate the weakness and negative influence of kinematics on patients with EP. Thus, Potential solutions are to constantly optimise freestyle swimming techniques and strengthen the arm muscles.

Breakfast Omission Reduces Subsequent Resistance Exercise Performance.

Bin Naharudin, MN, Yusof, A, Shaw, H, Stockton, M, Clayton, DJ, and James, LJ. Breakfast omission reduces subsequent resistance exercise performance. J Strength Cond Res 33(7): 1766-1772, 2019-Although much research has examined the influence of morning carbohydrate intake (i.e., breakfast) on endurance performance, little is known about its effects on performance in resistance-type exercise. Sixteen resistance-trained men (age 23 ± 4 years, body mass 77.56 ± 7.13 kg, and height 1.75 ± 0.04 m) who regularly (≥3 day/wk) consumed breakfast completed this study. After assessment of 10 repetition maximum (10RM) and familiarization process, subjects completed 2 randomized trials. After an overnight fast, subjects consumed either a typical breakfast meal (containing 1.5 g of carbohydrate/kg; breakfast consumption [BC]) or a water-only breakfast (breakfast omission [BO]). Two hours later, subjects performed 4 sets to failure of back squat and bench press at 90% of their 10RM. Sensations of hunger, fullness, desire to eat, and prospective food consumption were collected before, as well as immediately, 1 hour and 2 hours after BC/BO using 100-mm visual analogue scales. Total repetitions completed were lower during BO for both back squat (BO: 58 ± 11 repetitions; BC: 68 ± 14 repetitions; effect size [ES] = 0.98; p < 0.001) and bench press (BO: 38 ± 5 repetitions; BC: 40 ± 5 repetitions; ES = 1.06; p < 0.001). Fullness was greater, whereas hunger, desire to eat, and prospective food consumption were lower after a meal for BC compared with BO (p < 0.001). The results of this study demonstrate that omission of a pre-exercise breakfast might impair resistance exercise performance in habitual breakfast consumers. Therefore, consumption of a high-carbohydrate meal before resistance exercise might be a prudent strategy to help maximize performance.

Effects of isometric training and R.I.C.E. treatment on the arm muscle performance of swimmers with elbow pain.

The effects of IT and R.I.C.E. treatment on arm muscle performance in overhead athletes with elbow pain (EP) have been partially validated. However, there is a lack of research evidence regarding the efficacy of these two methods on arm muscle performance among swimmers with EP. The aim of this study was to investigate the trends and differences in the effects of IT and R.I.C.E. treatment on arm muscle performance among swimmers with EP. The main outcomes were the time effects and group effects of interventions on muscle voluntary contraction (MVC). Sixty elite freestyle swimmers from Tianjin, China, voluntarily participated in the study and completed a 10-week intervention program. Swimmers with EP in the IT group showed a positive trend in MVC, with an approximately 2% increase, whereas the MVC of subjects in the R.I.C.E. treatment group and control group decreased by approximately 4% and 5%, respectively. In comparison, the effects of the IT intervention on the MVC of the triceps and brachioradialis muscles in swimmers with EP were significant (p = 0.042 < 0.05, p = 0.027 < 0.05). The mean MVC value of the IT group (0.60) was greater than that of the other two groups (0.51, 0.50). IT has a beneficial impact on the MVC performance of the triceps and brachioradialis muscles in swimmers with EP. It is recommended that professionals consider incorporating IT into regular training routines to mitigate the risk of EP issues. Future research should examine the effectiveness of both interventions on hand-grip strength and completion time in 50-m freestyle swim drills in order for swimmers with EP to return to this sport.

Distribution and Prevalence of Elbow Pain (EP) in Elite Swimmers in Tianjin, China-A Regional Epidemiological Study.

Elbow pain (EP) in overhead sports is a common phenomenon. Swimming is classified as an overhead sport, but a lack of attention regarding EP in swimming has created a gap in the knowledge around elite freestyle swimming in Tianjin, China. The purpose of this study was to identify the distribution and prevalence of EP among elite freestyle swimmers in Tianjin, China. The methodology involved a total of 311 qualified participants who volunteered to undertake all measurements. The main findings showed that 183 of the elite freestyle swimmers in this study had EP (accounting for 58.84% of the total 311 participants), with 147 in slight pain and 36 in critical pain. The characteristics of a heavier body weight, taller height, longer left/right forearm length, and longer weekly average training hours serve as contributing factors to the occurrence of EP issues. Gender, age, weekly average training hours, and left/right forearm length are the primary factors correlating with and influencing the assessment scores. In conclusion, swimmers with longer weekly training hours, older ages, heavier bodyweight, and longer forearm lengths should receive greater attention in relation to EP. Regular assessments at a high frequency serve as a means to identify the risk of EP.

The effect of 10 days of energy-deficit diet and high-intensity exercise training on the plasma high-density-lipoprotein (HDL) level among healthy collegiate males.

ABSTRACTAn energy-deficit (ED) diet increases lipid mobilisation, while endurance exercise improves lipid profile by promoting formation of high-density lipoproteins (HDLs) among moderately active population. However, it is not clear whether ED with high-intensity exercise training can improve lipid profiles. Therefore, 20 recreationally active males (20.3 ± 2.7 years old with peak oxygen consumption (V˙O2peak) of 2.8 ± 0.2 L min-1) with HDL concentration of 1.44 ± 0.32 mmol L-1, were evenly allocated to either an ED group (1590 ± 79 kcal day-1: 40% of total caloric omitted at lunchtime) or a control (CON) group (2570 ± 139 kcal day-1). Participants in both groups performed high-intensity cycling at 90% V˙O2peak at a constant workload for 8 min, 2 h after breakfast on day D0, D2, D4, D6, D8 and D10 (Dn is day number), after which blood samples were collected. In ED, compared to D0, triglycerides (TG) decreased on D6-10 (p < .01) while total low-density lipoprotein (LDL), total cholesterol (TC) increased on D2-10, while HDL progressively increased on D6-10 (p = .01) with a final value of 1.67 ± 0.24 mmol L-1. In CON, there were no changes in TG, TC and HDL while LDL was reduced on D8-10 (p = .01). Moreover, the proportions of TC/HDL and LDL/HDL increased in ED on D2-10 and D2-8 (p = .05), respectively, while LDL/HDL in CON was reduced on D8-10 (p = .01). In brief, 10 days of ED and a series of high-intensity exercise sessions show progressive elevation of HDL which suggest longer period is required to observe changes in lipid ratios.

Analysis of Research Trends on Elbow Pain in Overhead Sports: A Bibliometric Study Based on Web of Science Database and VOSviewer.

The publications on elbow pain (EP) in overhead sports are increasing. The results of previous studies mostly focus on the influence of EP in the ball game and throwing sports. Thus, a bibliometric analysis of these publications may show the direction of hot topics and future research trends. The purpose of this study is to identify the research trends on EP in overhead sports. For the methods, the first step is to use the main keywords of 'Elbow pain' and 'Overhead sport' merging auxiliary vocabulary to reach the relevant global publications between 1970 and 2022 in the Web of Science (WoS) database. The literature data set is imported into EndNote literature manager software to remove duplication. Secondly, the duplication-reduced articles are imported to an Excel sheet according to the inclusion and exclusion criteria of this study. In the third step, VOSviewer software is applied as the main analysis tool in extracting data for analysis from the articles. Then, the main research results for three aspects are obtained by VOSviewer software which extracted and analyzed the parameters of author name, article title, publication journal, keywords, organization, publication country/region, and the sum of times cited from 455 qualified papers. The study found that the United States of America made the most outstanding contribution to this theme study. The research on EP in overhead sports in China requires more attention from scholars. EP in swimming is a new research direction worthy of attention. In conclusion, the research results prove the growth trend of EP in overhead sports. The EP problem not only exists in the ball game and throwing sports but also swimming. Sport commercialization and the involvement of related professional sports organizations determine the degree of EP's attention in a specific sport and the development of solutions. The development of a region or country also affects the depth and scope of EP study. Clinical research development and in-depth exploration are one of the bases to solve EP problems. Non-clinical action is beneficial to EP patients, but it still needs to be explored and studied.

Starving Your Performance? Reduced Preexercise Hunger Increases Resistance Exercise Performance.

BACKGROUND: Preexercise food intake enhances exercise performance due, in part, to the provision of exogenous carbohydrate. Food intake also suppresses hunger, but the specific influence of hunger on exercise performance has not been investigated. This study aimed to manipulate hunger by altering preexercise meal viscosity to examine whether hunger influences performance. METHODS: Sixteen resistance-trained males completed 2 experimental trials ingesting either high viscosity semisolid (SEM) and low viscosity liquid (LIQ) carbohydrate-containing meals 2 hours before performing 4 sets of back squat (85 [22] kg) and bench press (68 [13] kg) to failure at 90% 10-repetition maximum. Subjective hunger/fullness as well as plasma concentrations of glucose, insulin, ghrelin, and peptide tyrosine-tyrosine were measured before and periodically after the meal. Repetitions completed in sets were used to determine exercise performance. RESULTS: Hunger was lower, and fullness was greater during SEM compared with LIQ immediately before and during exercise (P < .05). Total repetitions completed for back squat were approximately 10% greater in SEM (SEM 57 [9]; LIQ 51 [7] repetitions; P = .001) with no difference in bench press repetitions (SEM 48 [11]; LIQ 48 [10] repetitions; P = .621). Postprandial glucose concentrations were greater during LIQ (12% increase in peak glucose) but were similar throughout exercise. CONCLUSION: This study demonstrates that exercise performance in back squat was increased in the SEM trial concomitant to a reduction in hunger. Therefore, this study provides novel data that suggest that exercise performance might be influenced by hunger, at least for resistance exercise.

The effect of 10 days of intermittent fasting on Wingate anaerobic power and prolonged high-intensity time-to-exhaustion cycling performance.

Many physically active individuals have undertaken intermittent fasting to reduce their daily caloric intake. However, abstaining from meals for a specific length of time may lead to the acute disturbance of highly carbohydrate-dependent exercise performance. The purpose of this study was to observe the effect of 10 days of intermittent fasting on high-intensity type exercises, Wingate anaerobic (WT) and prolonged high-intensity time-to-exhaustion (HIT) cycling test. Twenty participants were randomised into an intermittent fasting (FAS) and a control group (CON). One day after baseline data collection on Day-0 where participants consumed their recommended daily caloric intake (FAS = 2500 ± 143 kcal day-1; CON = 2492 ± 20 kcal day-1) served over a course of five meals, the FAS group consumed only four meals where 40% was restricted by the omission of lunch (FAS = 1500 ± 55 kcal day-1). This diet was then continued for 10 days. Data on exercise performance and other dependent variables were collected on Day-2, -4, -6, -8 and -10. A reduction in WT power in the FAS group was observed on Day-2 (821.74 ± 66.07 W) compared to Day-0 (847.63 ± 95.94 W) with a moderate effect size (p < .05, ES = 0.4), while HIT time-to-exhaustion performance declined over the 10 days with a trend of recovery from a large to a minimum effect size (p < .05, ES = 0.8-0.3). Body weight and triglyceride were consistently reduced in the FAS group (p < .01). The present study suggests that intermittent fasting must exceed 10 days to ensure that high-intensity performance does not deteriorate because this length of time seems to be required for effective adaptation to the new dietary regimen.

Fatigue index and fatigue rate during an anaerobic performance under hypohydrations.

BACKGROUND: Since hypohydration commonly occurs in sports, studies on anaerobic exercise performance under this condition have been extensively carried out. When describing anaerobic performance, authors usually refer to a drop in anaerobic performance as fatigue index (FI) which is conventionally calculated using peak and low power data points. Meanwhile, another possible method in explaining anaerobic fatigue is using the rate constant which is derived from the exponential decline of power output known as fatigue rate (FR). Few studies have demonstrated that there was no change in anaerobic performance under mild hypohydrations. PURPOSE: This study aimed to compare the kinetics of power output using FI and FR of an anaerobic performance (Wingate test) under 2, 3 and 4% state of hypohydrations. METHOD: Thirty two collegiate cyclists (age = 22 ± 2 years; body weight = 71.45 ± 3.43 kg; height = 173.23 ± 0.04 cm) were matched using their baseline anaerobic peak power (APP) then randomly divided into 4 groups of EU (euhydrated), 2H, 3H and 4H respectively. RESULTS: As expected the, FI, APP, anaerobic lower power (ALP) and rating of perceived exertion (RPE) did not show significant differences between and within the groups. However, the FR in 3H (0.018 ± 0.005 s(-1)) and 4H (0.019 ± 0.010 s(-1)) were significantly lower than EU (0.033 ± 0.012 s(-1)). Post-test FR also showed significant reduction in 3H and 4H compared to their pre-test values (p<0.05). CONCLUSION: Despite the lack of changes in APP and RPE, subjects in 3H and 4H showed evidence of lower reduction of power output over time. The findings support earlier reports which showed no change in anaerobic performance under mild hypohydrations. The relatively lower FR suggests higher drive in maintaining power output under hypohydrations of 3 and 4% body weight.