Kelly A. Barnes

The 'yips' in golf: a continuum between a focal dystonia and choking.

AbstractThe definition of the ‘yips’ has evolved over time. It is defined as a motor phenomenon of involuntary movements affecting golfers. In this paper, we have extended the definition to encompass a continuum from the neurologic disorder of dystonia to the psychologic disorder of choking. In many golfers, the pathophysiology of the ‘yips’ is believed to be an acquired deterioration in the function of motor pathways (e.g. those involving the basal ganglia) which are exacerbated when a threshold of high stress and physiologic arousal is exceeded. In other golfers, the ‘yips’ seems to result from severe performance anxiety. Physically, the ‘yips’ is manifested by symptoms of jerks, tremors or freezing in the hands and forearms. These symptoms can result in: (i) a poor quality of golf performance (adds 4.9 strokes per 18 holes); (ii) prompt use of alcohol and β-blockers; and (iii) contribute to attrition in golf. Golfers with the ‘yips’ average 75 rounds per year, although many ‘yips’-affected golfers decrease their playing time or quit to avoid exposure to this embarrassing problem. While more investigation is needed to determine the cause of the ‘yips’, this review article summarises and organises the available research. A small study included in this paper describes the ‘yips’ phenomenon from the subjective experience of ‘yips’-affected golfers. The subjective experience (n = 72) provides preliminary support for the hypothesis suggesting that the ‘yips’ is on a continuum. Based on the subjective definitions of 72 ‘yips’-affected golfers, the ‘yips’ was differentiated into type I (dystonia) and type II (choking). A theoretical model provides a guide for future research on golfers with either type I or type II ‘yips’.

Normative data for regional sweat sodium concentration and whole-body sweating rate in athletes

Abstract The purpose of this study was to establish normative data for regional sweat sodium concentration ([Na+]) and whole-body sweating rate in athletes. Data from 506 athletes (367 adults, 139 youth; 404 male, 102 female) were compiled from observational athlete testing for a retrospective analysis. The participants were skill/team-sport (including American football, baseball, basketball, soccer and tennis) and endurance (including cycling, running and triathlon) athletes exercising in cool to hot environmental conditions (15–50°C) during training or competition in the laboratory or field. A standardised regional absorbent patch technique was used to determine sweat [Na+] on the dorsal mid-forearm. Whole-body sweat [Na+] was predicted using a published regression equation (y = 0.57x+11.05). Whole-body sweating rate was calculated from pre- to post-exercise change in body mass, corrected for fluid/food intake (ad libitum) and urine output. Data are expressed as mean ± SD (range). Forearm sweat [Na+] and predicted whole-body sweat [Na+] were 43.6 ± 18.2 (12.6–104.8) mmol · L–1 and 35.9 ± 10.4 (18.2–70.8) mmol · L–1, respectively. Absolute and relative whole-body sweating rates were 1.21 ± 0.68 (0.26–5.73) L · h–1 and 15.3 ± 6.8 (3.3–69.7) ml · kg–1 · h–1, respectively. This retrospective analysis provides normative data for athletes’ forearm and predicted whole-body sweat [Na+] as well as absolute and relative whole-body sweating rate across a range of sports and environmental conditions.

Fluid Balance in Team Sport Athletes and the Effect of Hypohydration on Cognitive, Technical, and Physical Performance

Sweat losses in team sports can be significant due to repeated bursts of high-intensity activity, as well as the large body size of athletes, equipment and uniform requirements, and environmental heat stress often present during training and competition. In this paper we aimed to: (1) describe sweat losses and fluid balance changes reported in team sport athletes, (2) review the literature assessing the impact of hypohydration on cognitive, technical, and physical performance in sports-specific studies, (3) briefly review the potential mechanisms by which hypohydration may impact team sport performance, and (4) discuss considerations for future directions. Significant hypohydration (mean body mass loss (BML) >2%) has been reported most consistently in soccer. Although American Football, rugby, basketball, tennis, and ice hockey have reported high sweating rates, fluid balance disturbances have generally been mild (mean BML <2%), suggesting that drinking opportunities were sufficient for most athletes to offset significant fluid losses. The effect of hydration status on team sport performance has been studied mostly in soccer, basketball, cricket, and baseball, with mixed results. Hypohydration typically impaired performance at higher levels of BML (3–4%) and when the method of dehydration involved heat stress. Increased subjective ratings of fatigue and perceived exertion consistently accompanied hypohydration and could explain, in part, the performance impairments reported in some studies. More research is needed to develop valid, reliable, and sensitive sport-specific protocols and should be used in future studies to determine the effects of hypohydration and modifying factors (e.g., age, sex, athlete caliber) on team sport performance.

Trapped Sweat In Basketball Uniforms During Laboratory-based Intermittent Exercise: Effect Of Inter- And Intra-individual Factors: 654 June 1, 1: 00 PM - 1: 15 PM.

METHODS: The Runners And Injury Longitudinal Study (TRAILS) was a 2-year prospective observational study of 300 community recreational runners. Inclusion criteria included running a minimum of 5 miles/wk and injury free for at least the past 6 months. Data were collected on medical history, runners’ history, injury history, demographic information, medication use, and measuring height, weight, anthropometric measurements, 3-D gait analysis, isokinetic strength tests, pain scale, satisfaction with life, a quality of life (HRQL) scale (SF-12), and an affect scale (PANAS). Injuries were diagnosed by our orthopedic surgeon. RESULTS: The 300 runners included 174 males and 126 females; 275 (92%) of the 300 runners completed the study. 196 (65%) runners sustained at least 1 injury, including 71% of females and 61% of males. Significant (p ≤ 0.05) etiologic factors (M (SD)) across all injuries included: maximum vertical ground reaction force (N) (I: 1585 (296): NI: 1675 (297)), maximum propulsive force (N) (I: 179 (42): NI: 191 (42)), propulsive impulse (N*s) (I: 15 (4): NI: 16 (4)), tibiofemoral compressive force (N) (I: 6702 (1591): NI: 7093 (1537)), SF-12 mental component score (I: 48 (6): NI: 50 (3)), PANAS negative score (I: 15 (4): NI: 13 (3)), and age (yrs) (I: 42 (10): NI: 40 (11)).Q-angle (deg) (I: 15 (7): NI: 13 (7)), gender (more females injured), knee extensor (Nm) (I: 89 (41): NI: 101 (43)) and knee flexor strength (I: 54 (19): NI: 60 (20)) were additional significant factors for the most common injury locations (anterior knee, IT band, Achilles, plantar fascia, medial tibia). When only anterior knee pain was considered, patellofemoral compressive force (N) (I: 2725 (901): NI: 3088 (894)) and the SF-12 mental component (I: 47 (7): NI: 50 (3)) were the only significant factors. CONCLUSIONS: Characteristics of NI runners relative to all I runners included: greater ground reaction forces, higher tibiofemoral loads, younger, better mental health related quality of life, and lower negative affect.

Body map of regional vs. whole body sweating rate and sweat electrolyte concentrations in men and women during moderate exercise-heat stress

This study determined the relations between regional (REG) and whole body (WB) sweating rate (RSR and WBSR, respectively) as well as REG and WB sweat Na+ concentration ([Na+]) during exercise. Twenty-six recreational athletes (17 men, 9 women) cycled for 90 min while WB sweat [Na+] was measured using the washdown technique. RSR and REG sweat [Na+] were measured from nine regions using absorbent patches. RSR and REG sweat [Na+] from all regions were significantly ( P < 0.05) correlated with WBSR ( r = 0.58-0.83) and WB sweat [Na+] ( r = 0.74-0.88), respectively. However, the slope and y-intercept of the regression lines for most models were significantly different than 1 and 0, respectively. The coefficients of determination ( r2) were 0.44-0.69 for RSR predicting WBSR [best predictors: dorsal forearm ( r2 = 0.62) and triceps ( r2 = 0.69)] and 0.55-0.77 for REG predicting WB sweat [Na+] [best predictors: ventral forearm ( r2 = 0.73) and thigh ( r2 = 0.77)]. There was a significant ( P < 0.05) effect of day-to-day variability on the regression model predicting WBSR from RSR at most regions but no effect on predictions of WB sweat [Na+] from REG. Results suggest that REG cannot be used as a direct surrogate for WB sweating responses. Nonetheless, the use of regression equations to predict WB sweat [Na+] from REG can provide an estimation of WB sweat [Na+] with an acceptable level of accuracy, especially using the forearm or thigh. However, the best practice for measuring WBSR remains conventional WB mass balance calculations since prediction of WBSR from RSR using absorbent patches does not meet the accuracy or reliability required to inform fluid intake recommendations. NEW & NOTEWORTHY This study developed a body map of regional sweating rate and regional (REG) sweat electrolyte concentrations and determined the effect of within-subject (bilateral and day-to-day) and between-subject (sex) factors on the relations between REG and the whole body (WB). Regression equations can be used to predict WB sweat Na+ concentration from REG, especially using the forearm or thigh. However, prediction of WB sweating rate from REG sweating rate using absorbent patches does not reach the accuracy or reliability required to inform fluid intake recommendations.

Trapped sweat in basketball uniforms and the effect on sweat loss estimates

The aims of this study were to determine: (1) trapped sweat (TS) in basketball uniforms and the effect on sweat loss (SL) estimates during a laboratory‐based basketball simulation protocol; (2) the impact of exercise intensity, body mass, age, and SL on TS; and (3) TS during on‐court training to assess the ecological validity of the laboratory‐based results. Twenty‐four recreational/competitive male basketball players (23 ± 10 years, 77.0 ± 16.7 kg) completed three randomized laboratory‐based trials (Low, Moderate, and High intensity) consisting of 150‐min intermittent exercise. Eighteen elite male players (23 ± 4 years, 92.0 ± 20.6 kg) were observed during coach‐led, on‐court training. Nude and clothed body mass were measured pre and postexercise to determine TS. Data are mean ± SD. There was a significant effect of intensity on SL and TS (P < 0.001, Low