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1.
Bone Joint J ; 95-B(11): 1508-13, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24151271

ABSTRACT

The aim of this study was to determine the effect of a Galeazzi fracture on the strength of pronation and supination at a mean of two years after surgical treatment. The strength of pronation and supination was measured in varying rotational positions of the forearm of ten male patients (mean age 38.9 years (21 to 64)) who had undergone plate fixation for a Galeazzi fracture. The stability of the distal radioulnar joint was assessed, and a clinical assessment using the quick-Disabilities of the Arm Shoulder and Hand (quickDASH) questionnaire and patient-related wrist examination (PRWE) scores was undertaken. In addition, the strength of pronation and supination was measured in a male control group of 42 healthy volunteers (mean age 21.8 years (18 to 37)). The mean absolute loss of strength of supination in the injured compared with the non-injured arm throughout all ranges of forearm rotation was 16.1 kg (sem 5.3), corresponding to a relative loss of 12.5% (95% confidence interval (CI) 3.6 to 21.4). For the strength of pronation, the mean loss was 19.1 kg (sem 4.5), corresponding to a relative loss of 27.2% (95% CI 14.2 to 40.1). Loss of strength of supination following a Galeazzi fracture correlated with poor quickDASH (p = 0.03) and PRWE scores (p < 0.01). Loss of strength of pronation (27.2%), and of supination (12.5%) in particular, after a Galeazzi fracture is associated with worse clinical scores, highlighting the importance of supination of the forearm in function of the upper limb.


Subject(s)
Pronation/physiology , Radius Fractures/physiopathology , Radius Fractures/surgery , Supination/physiology , Wrist Joint/physiopathology , Adolescent , Adult , Bone Plates , Disability Evaluation , Female , Follow-Up Studies , Fracture Fixation, Internal , Humans , Male , Middle Aged , Prognosis , Range of Motion, Articular/physiology , Surveys and Questionnaires , Treatment Outcome , Wrist Joint/surgery , Young Adult
2.
Res Sports Med ; 20(3-4): 239-62, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22742078

ABSTRACT

Anterior cruciate ligament (ACL) injury rates have increased by ∼50% over the last 10 years. These figures suggest that ACL focused research has not been effective in reducing injury rates among community level athletes. Training protocols designed to reduce ACL injury rates have been both effective (n = 3) and ineffective (n = 7). Although a rationale for the use of exercise to reduce ACL injuries is established, the mechanisms by which they act are relatively unknown. This article provides an injury prevention framework specific to noncontact ACL injuries and the design of prophylactic training protocols. It is also apparent that feedback within this framework is needed to determine how biomechanically relevant risk factors like peak joint loading and muscular support are influenced following training. It is by identifying these links that more effective ACL injury prevention training programs can be developed, and, in turn, lead to reduced ACL injury rates in the future.


Subject(s)
Anterior Cruciate Ligament Injuries , Athletic Injuries/prevention & control , Athletic Injuries/etiology , Evidence-Based Practice , Female , Humans , Male , Models, Theoretical , Physical Education and Training/methods
3.
Knee ; 19(4): 431-9, 2012 Aug.
Article in English | MEDLINE | ID: mdl-21782452

ABSTRACT

PURPOSE: There is no ideal treatment for younger patients with medial knee osteoarthritis (OA) and varus malalignment. We have investigated the first case series of combined neutralising high tibial osteotomy (HTO) and Matrix-induced Autologous Chondrocyte Implantation (MACI) with MRI. Treatment goals were clinical improvement and delay of arthroplasty. METHODS: Between 2002 and 2005 18 patients (Mean age 47 years) underwent surgery. Exclusion criteria were lateral compartment and advanced patellofemoral OA. The Knee Injury and Osteoarthritis Outcome Score (KOOS), six minute walk test (6MWT) and a validated MRI score were outcome measures. RESULTS: There were significant improvements (p<0.05) in all five KOOS domains. Four were significantly maintained to 5 years. The domain "symptoms" and results in the 6MWT dropped off at 5 years. MRI results were first significantly improved (24/12) but declined at 60 months. Good quality infill was found in 33% patients at the study endpoint (n=5/15). Histological investigation of one knee demonstrated full-thickness hyaline-like cartilage (20/12). After 2 early failures and one graft detachment graft fixation was changed (Smart nails instead of sutures in 14 cases). Graft hypertrophy requiring a chondroplasty occurred once. There were no other major complications. Specific minor complications included patellar tendinitis (n=8). CONCLUSIONS: This combined procedure provides a safe treatment option for younger patients with medial knee OA and varus alignment with significant clinical improvement at 5 years. However, overall graft survival and cartilage infill were poor. Larger studies are needed to statistically verify predictors for longer term cartilage repair in these patients.


Subject(s)
Chondrocytes/transplantation , Osteoarthritis, Knee/surgery , Osteotomy/methods , Adult , Cartilage, Articular/pathology , Combined Modality Therapy , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged
4.
Int J Obes (Lond) ; 35(6): 810-9, 2011 Jun.
Article in English | MEDLINE | ID: mdl-20938438

ABSTRACT

BACKGROUND: Regular consumption of diets with increased protein or fibre intakes may benefit body weight and composition and cardiovascular disease risk factors. Lupin flour is a novel food ingredient high in protein and fibre. OBJECTIVE: To investigate the effects of a lupin-enriched diet, during and following energy restriction, on body weight and composition and cardiovascular disease risk factors in overweight individuals. DESIGN: Participants (n = 131) were recruited to a 12-month parallel-design trial. They were randomly assigned to consume lupin-enriched foods or matching high-carbohydrate control foods. All participants underwent 3 months of weight loss, 1 month of weight stabilization and 8 months of weight maintenance. Body weight and composition and cardiovascular disease risk factors were assessed at baseline, 4 and 12 months. RESULTS: Lupin, relative to control, did not significantly influence (mean difference (95% CI)) weight loss at 4 months (0.1 kg (-1.2, 1.4)) and 12 months (-0.6 kg (-2.0, 0.8)), maintenance of weight loss from 4 to 12 months (-0.7 kg (-1.83, 0.48)) or measures of body fat and fat-free mass. Relative to control, 24-h ambulatory systolic (-1.3 mm Hg (-2.4, -0.3), P = 0.016) and diastolic (-1.0 mm Hg (-1.9, -0.2), P = 0.021) blood pressures were lower at 12 months but not at 4 months; fasting insulin concentrations and homeostasis model assessment (HOMA) scores were significantly lower at 4 months (-1.2 mU l(-1) (-1.3, -1.1), P = 0.004 and -0.6 units (-1.0, -0.19), P = 0.004) and 12 months (-1.3 mU l(-1) (-1.4, -1.1), P < 0.001 and -0.7 units (-1.1, -0.24), P = 0.002). CONCLUSIONS: A diet higher in protein and fibre derived from lupin-enriched foods does not enhance weight loss or improve the maintenance of weight loss. However, such a diet may provide cardiovascular health benefits in terms of insulin sensitivity and blood pressure.


Subject(s)
Body Composition/physiology , Caloric Restriction/methods , Cardiovascular Diseases/prevention & control , Dietary Fiber/administration & dosage , Dietary Proteins/administration & dosage , Lupinus/physiology , Weight Loss/physiology , Adult , Aged , Blood Pressure/physiology , Cardiovascular Diseases/blood , Diet , Dietary Carbohydrates/administration & dosage , Dietary Fiber/metabolism , Dietary Proteins/metabolism , Double-Blind Method , Energy Intake/physiology , Female , Humans , Insulin/blood , Lupinus/metabolism , Male , Middle Aged , Risk Factors
5.
Int J Obes (Lond) ; 34(6): 1086-94, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20157326

ABSTRACT

BACKGROUND: Lupin kernel flour (LKF) is a novel food ingredient that is high in protein and fibre. We have previously shown that partial substitution of refined wheat-derived carbohydrate in bread with protein and fibre from LKF can reduce appetite and energy intake acutely. In addition, several studies have suggested that lupin may reduce cholesterol concentrations and benefit glucose and insulin metabolism. AIM: The aim of this study was to investigate the effects on body weight and composition and blood lipids, glucose and insulin of an ad libitum LKF-enriched diet higher in dietary protein and fibre. SUBJECTS AND METHODS: A total of 88 overweight and obese men and women were recruited for a 16-week parallel-design randomized controlled trial. Participants replaced 15-20% of their usual daily energy intake with white bread (control) or LKF-enriched bread (lupin) in an ad libitum diet. Measurements of body weight and composition, and fasting blood biochemical measurements were performed at baseline and 16 weeks. The primary analysis included 74 participants (37 per group) who completed the intervention. RESULTS: At baseline, mean (+/-s.d.) body mass index and total cholesterol were 30.6+/-3.5 kg m(-2) and 5.37+/-0.94 mmol l(-1), respectively. Estimated (mean between-group difference (95% confidence interval)) protein (13.7 (2.28, 25.0) g per day) and fibre (12.5 (8.79, 16.2) g per day) intakes were higher during the intervention with lupin than with control. For lupin relative to control, the net effects on body weight (-0.4 (-1.3, 0.6) kg), fat mass (-0.5 (-1.1, 0.2) kg) and percentage (-0.5 (-1.1, 0.1)%), plasma leptin (-1.66 (-4.91, 1.59) ng ml(-1)) and adiponectin (0.20 (-0.73, 1.13) mg l(-1), as well as serum total cholesterol (-0.08 (-0.38, 0.22) mmol l(-1)), triglycerides (0.09 (-0.10, 0.21) mmol l(-1)), glucose (0.10 (-0.11, 0.30) mmol l(-1)) and insulin (0.40 (-1.20, 2.00) mU l(-1)) were not significant. CONCLUSIONS: This study does not support the proposal that an ad libitum diet enriched in LKF resulting in moderate changes in both protein and fibre intakes can benefit body weight and composition or fasting blood lipids, glucose and insulin concentrations in overweight men and women with mildly elevated total cholesterol concentrations.


Subject(s)
Body Weight/physiology , Dietary Fiber/administration & dosage , Dietary Proteins/administration & dosage , Energy Intake/physiology , Lipids/blood , Lupinus , Overweight/blood , Adult , Aged , Blood Glucose/metabolism , Body Mass Index , Bread , Diet , Dietary Carbohydrates/blood , Dietary Proteins/blood , Female , Humans , Leptin/blood , Male , Middle Aged , Overweight/diet therapy , Overweight/physiopathology , Triglycerides/blood
6.
Osteoporos Int ; 21(9): 1529-36, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20091404

ABSTRACT

SUMMARY: A 1-year randomized controlled trial of resistance training compared with a control group was undertaken in 143 men aged 55-80 years. Although hip bone mineral density, lean body mass, and function increased in both groups, lean body mass and function but not bone density increased more in the resistance group. INTRODUCTION: Previous studies have demonstrated a positive effect of resistance training on bone mineral density (BMD) in postmenopausal women, but the effect in men is unclear. The aim was to examine the effect of a 1-year resistance training program on bone and lean body mass in 143 men aged 55-80 years, randomized to either resistance training or active control. METHODS: Resistance exercises were selected to provide loading at the hips. Measurements were taken at 0, 6, and 12 months for BMD (whole body, hip, and spine), lean body mass, strength, and functional fitness. RESULTS: The intervention showed a significant increase in total hip BMD for both groups at 12 months (active control, 1,014-1,050 mg/cm(2); resistance, 1,045-1,054 mg/cm(2), p < 0.05) with no increased effect of resistance training compared to active control. However, compared to the active control group, the resistance group increased their lean body mass (active control, 0.1 +/- 2.1%; resistance, 1.5 +/- 2.7%, p < 0.05), fitness (active control, 4.6 +/- 11.1%; resistance, 13.0 +/- 13.4%, p < 0.05), and lower limb muscle strength (active control, 14.3 +/- 16.8%; resistance, 39.4 +/- 30.87%, p < 0.05). CONCLUSIONS: In contrast to previous findings in older women, in older men, a resistance training program does not increase hip bone mass more than walking 30 min three times a week.


Subject(s)
Lower Extremity/physiology , Muscle, Skeletal/physiology , Resistance Training/methods , Aged , Aged, 80 and over , Anthropometry/methods , Body Composition/physiology , Body Mass Index , Bone Density/physiology , Follow-Up Studies , Hip Joint/physiology , Humans , Lumbar Vertebrae/physiology , Male , Middle Aged , Muscle Strength/physiology
7.
Knee ; 14(2): 117-27, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17257849

ABSTRACT

We present our experience with the collagen-covered autologous chondrocyte implantation (CACI) technique. Thirty two implantations were performed in 31 patients. Clinical outcome was measured using the KOOS score and the 6-minute walk test, as well as an MRI scoring protocol (75% of patients had a complete data set for MRI follow-up) to describe the repair tissue generated by CACI. We have also correlated our MRI results with our clinical outcome. To the authors knowledge there are no comparative studies of MRI and clinical outcome following CACI in the current literature. Patients demonstrated an increased walk distance that improved significantly from 3 months to 24 months postoperatively (p<0.05). Analysis of the KOOS results demonstrated a significant (p<0.05) improvement in four of the five subscales from 3 months to 24 months after CACI, with the most substantial gains made in the first 12 months. Patients demonstrated an increased MRI outcome score over time that improved significantly from 3 months to 24 months postoperatively (p<0.05). We observed an 8% incidence of hypertrophic growth following CACI. We report one partial graft failure, defined by clinical, MRI and histological evaluation, at the one year time point. In contrast to the current literature we report no incidence of manipulation under anesthesia (MUA) following CACI. This research demonstrates that autologous chondrocytes implanted under a type I/III collagen patch regenerates a functional infill material, and as a result of this procedure, patients experienced improved knee function and MRI scores. Whilst our results indicated a statistically significant relationship between the MRI and functional outcome following CACI, MRI cannot be used as surrogate measure of functional outcome following CACI, since the degree of association was only low to moderate. That is, functional outcome following CACI cannot be predicted by the morphological MRI assessment of the repair tissue at the post-surgery time points to 24 months.


Subject(s)
Chondrocytes/transplantation , Collagen Type III/therapeutic use , Collagen Type I/therapeutic use , Knee Joint/pathology , Knee Joint/surgery , Adult , Cartilage, Articular/pathology , Cartilage, Articular/surgery , Follow-Up Studies , Humans , Magnetic Resonance Imaging , Transplantation, Autologous , Treatment Outcome
8.
J Sports Sci ; 25(1): 43-53, 2007 Jan 01.
Article in English | MEDLINE | ID: mdl-17127580

ABSTRACT

Rowers competing at the 2000 Olympic Games were measured for 38 anthropometric dimensions. The aim was to identify common physical characteristics that could provide a competitive advantage. The participants included 140 male open-class rowers, 69 female open-class rowers, 50 male lightweight rowers, and 14 female lightweight rowers. Body mass, stature, and sitting height were different (P < 0.01) between the open-class and lightweight rowers, as well as a comparison group of healthy young adults ("non-rowers", 42 males, 71 females), for both sexes. After scaling for stature, the open-class rowers remained proportionally heavier than the non-rowers, with greater proportional chest, waist, and thigh dimensions (P < 0.01). Rowers across all categories possessed a proportionally smaller hip girth than the non-rowers (P < 0.01), which suggested the equipment places some constraints on this dimension. Top-ranked male open-class rowers were significantly taller and heavier and had a greater sitting height (P < 0.01) than their lower-ranked counterparts. They were also more muscular in the upper body, as indicated by a larger relaxed arm girth and forearm girth (P < 0.01). For the male lightweight rowers, only proportional thigh length was greater in the best competitors (P < 0.01). In the female open-class rowers, skinfold thicknesses were lower in the more highly placed competitors (P < 0.01). In conclusion, the rowers in this sample demonstrated distinctive physical characteristics that distinguish them from non-rowers and other sports performers.


Subject(s)
Anthropometry , Body Size/physiology , Sports/physiology , Adult , Body Composition/physiology , Case-Control Studies , Female , Humans , Male , Skinfold Thickness , Somatotypes/physiology
9.
J Sports Sci ; 23(10): 1057-63, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16194982

ABSTRACT

The aim of this study was to compare the somatotype and size of elite female basketball players in terms of playing position and team performance. Anthropometry and somatotype data were collected on 168 players from 14 countries before the Women's World Basketball Championship, Australia, 1994. There were 64 guards (mean +/- s: age 25.4 +/- 3.3 years, height 1.72 +/- 0.06 m, mass 66.1 +/- 6.2 kg, somatotype = 2.9-3.9-2.6), 57 forwards (age 25.2 +/- 3.8 years, height 1.81 +/- 0.06 m, mass 73.3 +/- 5.9 kg, somatotype = 2.8-3.5-3.2) and 47 centres (age 24.1 +/- 3.1 years, height 1.90 +/- 0.06 m, mass 82.6 +/- 8.2 kg, somatotype = 3.2-3.1-3.4). Mean somatotypes by position were significantly different (F = 7.73, P < 0.01). Guards had greater mesomorphy than centres and less ectomorphy than forwards and centres. When discriminant function analysis was applied to endomorphy, mesomorphy, ectomorphy, age, height and mass, only height, mass and ectomorphy entered (Wilks' lambda = 0.351, F = 31.40, P < 0.000), 70% of the variance was accounted for, and 72% of players were correctly classified. In the four top versus four bottom teams, guards were taller and more ectomorphic, forwards were taller, with lower mesomorphy and higher ectomorphy, and centres did not differ. Thus there are some differences in somatotypes by position and team placing, but the combination of height, mass and ectomorphy provide the best differentiation by position.


Subject(s)
Basketball/physiology , Body Size/physiology , Somatotypes , Adult , Analysis of Variance , Female , Humans , Internationality
10.
Sports Biomech ; 4(1): 47-58, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15807376

ABSTRACT

The anthropometry and equipment set-up for sprint (31 male; 11 female) and slalom (12 male; 12 female) kayak paddlers who competed at the 2000 Olympic Games in Sydney were measured in the 15 day period before competition. This paper provides normative data for equipment set-up in these sports, as well as information about differences in rigging and paddle dimensions between sprint and slalom kayak paddlers. These differences were consistent for both male and female athletes, with sprint paddlers seated higher and using longer paddles with longer, though narrower, blades (p < 0.0001). Among male sprint paddlers, only minor differences in equipment set-up were found between competitors ranked in the top 10 places compared to the rest of the field. Considering all male paddlers initially, then sprint paddlers alone, significant (p < 0.01) regression equations were developed for the prediction of foot bar distance (r2 = 0.482 and 0.589 respectively) and hand grip distance (r2 = 0.400 and 0.541 respectively). The process of fine tuning equipment set-up often requires hours of practice with subjective feedback from the athlete. The normative data presented in this paper should assist coaches with this process as their athletes evolve toward their individual optimum set-up.


Subject(s)
Ships/instrumentation , Sports Equipment , Sports/physiology , Adult , Body Size , Competitive Behavior , Equipment Design , Ergonomics , Female , Humans , Male , Regression Analysis , Sex Factors
11.
J Sci Med Sport ; 6(3): 285-94, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14609145

ABSTRACT

Canoe and kayak paddlers (n = 50 M & 20 F) who competed in the sprint events at the 2000 Olympic Games in Sydney were measured on a battery of 38 anthropometry dimensions prior to competition. The ensuing analysis aimed to identify common physical characteristics that provide these elite paddlers with a competitive advantage. This study demonstrated that participants in Olympic sprint paddling events can be considered homogeneous in shape and physical size; male and female paddlers have SAMs of 1.1 and 1.0 respectively. Compared to other athlete groups, the variance in stature and body mass of paddlers is generally low. Whilst sprint paddlers are not athletes with extreme proportionality profiles, they do possess unique characteristics not commonly observed in the general population. These include a lean body composition (Phantom z-scores for skinfolds range from -1.5 to -2.5 for most sites) with proportionally large upper body girths (z-scores > +1.0 for arm and chest girths), and narrow hips (for males). The morphology of elite paddlers appears to have altered during the past 25 years toward a more compact, robust physique. This trend is especially noticeable for the female competitors.


Subject(s)
Anthropometry , Sports/physiology , Adult , Age Factors , Australia , Canada , Female , Humans , Male , Sex Factors , Somatotypes/physiology
12.
Med Sci Sports Exerc ; 33(7): 1176-81, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11445765

ABSTRACT

PURPOSE: To determine how unanticipated performance of cutting maneuvers in sport affects the external loads applied to the knee joint and the potential risk for ligament injury. METHODS: A 50-Hz VICON motion analysis system was used to determine the lower limb kinematics of 11 healthy male subjects during running and cutting tasks performed under preplanned (PP) and unanticipated (UN) conditions. Subjects performed the UN tasks in response to a light stimulus on a target board. A kinematic model was then used in conjunction with force place data to calculate the three-dimensional loads at the knee joint. RESULTS: External flexion/extension moments at the knee joint were similar between PP and UN conditions; however, the varus/valgus and internal/external rotation moments during the UN cutting tasks were up to twice the magnitude of the moments measured during the PP condition. CONCLUSION: Cutting maneuvers performed without adequate planning may increase the risk of noncontact knee ligament injury due to the increased external varus/valgus and internal/external rotation moments applied to the knee. These results are probably due to the small amount of time to make appropriate postural adjustments before performance of the task, such as the position of the foot on the ground relative to the body center of mass. Subsequently, training for the game situation should involve drills that familiarize players with making unanticipated changes of direction. Practice sessions should also incorporate plyometrics and should focus on better interpretation of visual cues to increase the time available to preplan a movement.


Subject(s)
Gait/physiology , Knee Joint/physiology , Psychomotor Performance/physiology , Running/physiology , Weight-Bearing/physiology , Adolescent , Adult , Biomechanical Phenomena , Humans , Knee Injuries/physiopathology , Male , Rotation , Soccer/physiology
13.
Med Sci Sports Exerc ; 33(7): 1168-75, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11445764

ABSTRACT

PURPOSE: To investigate the external loads applied to the knee joint during dynamic cutting tasks and assess the potential for ligament loading. METHODS: A 50-Hz VICON motion analysis system was used to determine the lower limb kinematics of 11 healthy male subjects during running, sidestepping, and crossover cut. A kinematic model was used in conjunction with force place data to calculate the three-dimensional loads at the knee joint during stance phase. RESULTS: External flexion/extension loads at the knee joint were similar across tasks; however, the varus/valgus and internal/external rotation moments applied to the knee during sidestepping and crossover cutting were considerably larger than those measured during normal running (P < 0.05). Sidestepping tasks elicited combined loads of flexion, valgus, and internal rotation, whereas crossover cutting tasks elicited combined loads of flexion, varus, and external rotation. CONCLUSION: Compared with running, the potential for increased ligament loading during sidestepping and crossover cutting maneuvers is a result of the large increase in varus/valgus and internal/external rotation moments rather than any change in the external flexion moment. The combined external moments applied to the knee joint during stance phase of the cutting tasks are believed to place the ACL and collateral ligaments at risk of injury, particularly at knee flexion angles between 0 degrees and 40 degrees, if appropriate muscle activation strategies are not used to counter these moments.


Subject(s)
Gait/physiology , Knee Joint/physiology , Running/physiology , Weight-Bearing/physiology , Adolescent , Adult , Biomechanical Phenomena , Humans , Knee Injuries/physiopathology , Male , Rotation , Soccer/physiology
14.
Article in English | MEDLINE | ID: mdl-11282314

ABSTRACT

To investigate the combined use of an interactive racecar simulator and heat acclimation on psychomotor (driving) performance, eight rally drivers underwent 4 days of repeated heat (50 degrees C) exposure (1 h x day(-1)) during which they performed a simulated rally drive (3x12-min stages each separated by a 2-min break), after first cycling for 15 min at 125 W to induce some degree of fatigue and heat storage prior to beginning the rally. During the rally stages, a generic set of pace notes were read to the subject by a co-driver. In each simulation, sweat loss, heart rate, core (rectal) and skin temperatures were recorded and driving and psychomotor performance were assessed by recording stage times and time to complete a psychomotor test. Levels of physiological and perceived thermal strain were also recorded. Significant decreases in rally stage times (88 s; P<0.005), psychomotor test time (18 s; P<0.01), final core (0.25 degrees C; P<0.001) and skin (0.44 degrees C; P<0.005) temperatures, heart rate (16 beats x min(-1); P<0.05) and physiological (15 W x m(-2); P<0.005) and perceived thermal (3.7 units; P<0.01) strain were evident by the end of the final simulation, and a significant (P<0.05) increase in sweat sensitivity (+0.33 g x h(-1) x degrees C(-1)) was also recorded. These results suggest that both heat acclimation and race simulation can improve the psychomotor performance of rally drivers, although the relative contribution of each factor was not determined here. However, in a practical setting, these factors would not be used in isolation. After performing the acclimation and simulation protocol prior to an actual rally, drivers subjectively reported improvements in tolerating a high thermal load and in their ability to control the rally vehicle.


Subject(s)
Adaptation, Physiological , Automobile Driving , Hot Temperature , Sports Medicine , Adult , Body Temperature Regulation , Humans , Male , Psychomotor Performance , Sweating
15.
Article in English | MEDLINE | ID: mdl-11282315

ABSTRACT

Two of the major stressors endured by a motorsport athlete (MSA) during a racing event are the effects of heat and carbon monoxide. To date, there has been little research into their combined effect on driving performance. Using an interactive racecar simulator located within an environmental chamber, subjects drove a simulated race (60 min) in environmental conditions similar to those that develop during a NASCAR Winston Cup oval track race (50 degrees C ambient temperature and 10-12% carboxyhaemoglobin levels). Subjects also completed cool (20 degrees C) and heat only (50 degrees C) race simulations. During the simulations, oxygen consumption, heart rate, core and skin temperatures and psychomotor performance were measured. The results demonstrated that exposure to a racecar micro-environment combining both heat and CO produced significantly greater (P<0.05) sweat loss and core temperature change (1.53 kg; 1.06 degrees C) when compared to the heat only (1.14 kg; 0.73 degrees C) and cool conditions (0.35 kg; 0.09 degrees C). Furthermore, a significant decrease (P<0.05) in psychomotor performance was also shown between the heat/CO condition (contact points=38), and both the heat only (25 points) and cool conditions (22 points). It follows that lengthy exposure to these two stressors could produce a substantial decrement in driving performance, thereby endangering the MSA and other race competitors.


Subject(s)
Automobile Driving , Carbon Monoxide/adverse effects , Hot Temperature/adverse effects , Sports , Accidents, Traffic , Adult , Body Temperature Regulation , Heart Rate , Humans , Psychomotor Performance , Sweating
16.
Ann Hum Biol ; 27(4): 387-400, 2000.
Article in English | MEDLINE | ID: mdl-10942346

ABSTRACT

Performance is related to body morphology in many sports. With triathlon making its debut into the Olympic programme in 2000, it was deemed important to determine which physical characteristics of elite-level triathletes were significantly related to performance. Seventy-one elite and junior elite triathletes, from 11 nations, competing at the 1997 World Triathlon Championships were measured on a battery of 28 anthropometric dimensions. A factor analysis was conducted, which reduced the number of variables to four and these were used in a stepwise linear regression to determine which morphological factors were important to performance. Elite triathletes were significantly (p < 0.05) faster than their junior counterparts (males 1:52:26 vs. 2:03:23 and females 2:07:01 vs. 2:14:05) and showed less variation in performance times. Run time variation was the largest of the component disciplines and tended to show the importance of this discipline to the final outcome. Following a factor analysis the four distinguishable morphological factors that emerged were: robustness, adiposity, segmental lengths and skeletal mass. Relating these factors to the total time obtained by the triathletes in this study yielded a regression equation that correlated significantly with all triathletes, accounting for 47% of the variance in total triathlon duration. The regression equations illustrated the importance of low levels of adiposity for elite triathletes for total time and most of the subdisciplines. The other factor that showed importance was that proportionally longer segmental lengths contributed to successful swimming outcome.


Subject(s)
Bicycling/physiology , Physical Endurance/physiology , Running/physiology , Swimming/physiology , Adult , Female , Humans , Linear Models , Male , Time Factors
18.
J Sports Sci ; 16(4): 317-29, 1998 May.
Article in English | MEDLINE | ID: mdl-9663956

ABSTRACT

The aim of this study was to evaluate sexual dimorphism in male (n = 43) and female (n = 39) springboard and platform divers at the 1991 World Diving Championships in Perth, Western Australia. In addition to recording the age, height and body mass of each diver, measurements were taken of 8 skinfolds, 13 girths, 8 breadths and depths, and 11 lengths. The derived variables were somatotype, sum of 6 skinfolds (SUM6) and height-adjusted proportional z-scores. The mean (+/- s) values for the males were: age, 22.2 +/- 4.6 years; height, 171 +/- 9 cm; body mass, 66.7 +/- 10.2 kg; somatotype, 2.0-5.3-2.4 +/- 0.5-1.0-0.8; SUM6, 45.9 +/- 11.4 mm. For the females, these values were: age, 20.9 +/- 3.8 years; height, 161 +/- 6 cm; body mass, 53.7 +/- 5.5 kg; somatotype, 2.8-3.8-2.8 +/- 0.7-1.0-0.9; SUM6, 65.6 +/- 17.0 mm. The males were taller, heavier, more mesomorphic, less endomorphic and had a smaller SUM6 than the females (P < 0.01). A series of discriminant function analyses were applied to groups of variables. Wilks' lambda and the overall F-ratio were highly significant (P < 0.001), with correct classification of sex reaching 84-99%. The best combinations of variables were as follows: (1) absolute size, 3 girths + SUM6, or body mass + SUM6 + height (Wilks' lambda = 0.17-0.35); (2) relative size, 2 girths + SUM6 + body mass. Combinations of breadths and lengths, skinfolds, or somatotype components, were less successful, with 84-87% classified correctly (Wilks' lambda = 0.40-0.48). We conclude that, in addition to the expected absolute size differences, sexual dimorphism between male and female divers can be explained by differences in relative size, skinfolds and somatotype, and that these differences may have implications for coaching and selection in diving.


Subject(s)
Diving/physiology , Sex Characteristics , Adult , Biomechanical Phenomena , Competitive Behavior , Discriminant Analysis , Female , Humans , Male , Skinfold Thickness , Somatotypes
20.
J Sports Sci ; 15(5): 485-90, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9386206

ABSTRACT

In total, 168 players from 14 national teams were measured using 38 anthropometric dimensions before the Women's World Basketball Championships held in Australia in 1994. Measures of segment length, breadth and girth were recorded by a team of trained anthropometrists using standard protocols. The subjects were divided according to playing position and team performance so that univariate analyses of variance could be administered using absolute size and proportionality data as dependent variables. Clear differences in absolute size were found between guards, forwards and centres, but in terms of proportionality the latter two groups exhibited some similarities, particularly for measures of relative size in upper body dimensions. With guards displaying a different proportionality profile from either forwards or centres, the various roles of each position within the team were considered to rationalize the findings.


Subject(s)
Anthropometry , Basketball/physiology , Physical Endurance , Adult , Analysis of Variance , Body Height , Body Weight , Female , Humans , Reference Values
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