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PubMedDate not supplied

Modelling the relationships between training, anxiety, and fatigue in elite athletes.

This study investigated the effects of 40-week training on anxiety and perceived fatigue in four elite triathletes. Anxiety and perceived fatigue were self-reported by the subjects twice a week by the way of a specific questionnaire and were linked by a mathematical model to the training loads calculated from the exercise heart rate. A significant relationship (r=0.32; p<0.001) between the training loads and anxiety was identified using a two-component model: a first, negative (i.e., anxiety decreased) short-term (tau (1)=23 days) function and a second, positive long-term (tau (2)=59 days) function. The relationship between the training loads and perceived fatigue was significant (r=0.30; p<0.001), with one negative function (tau (1)=4 days). This mathematical model can potentially describe the relationships between training loads and anxiety or perceived fatigue and may improve both the adjustment of the duration of tapering and the early detection of staleness.

Adult↗
PubMedDate not supplied

Heart rate responses during a breath-holding competition in well-trained divers.

The diving response elicited by breath-holding (BH) and immersion mainly consists of bradycardia, decreased cardiac output, and peripheral vasoconstriction. These responses reduce oxygen consumption and thereby prolong the duration of the dive. They may also lead to cardiac arrhythmias or hypoxia, however, which in turn may play a role in the occurrence of syncope during BH. The aim of the present study was to analyze the cardiac responses to prolonged breath-holding in elite divers during a competition. Heart rate behaviour and the incidence of arrhythmia were recorded in 16 well-trained breath-hold divers (BHD) using a cardio-frequency meter (for 15 divers) and a Holter (for one diver) during maximal static breath-holding. Anthropometric, spirometric, and training characteristics such as percentage of body fat, pulmonary volumes and years of BH training were also determined. Forced vital capacity (FVC) and forced expiratory volume in one second (FEV (1)) were higher than the predicted values (+7.7%, p<0.05 and+6.6%, p<0.05, respectively). During the static BH, divers presented apneic bradycardia (-44%) correlated with static BH times (p<0.05); this was associated with cardiac arrhythmias (supraventricular extrasystoles and ventricular extrasystoles) in the Holter-equipped subject. These results are in agreement with those obtained in laboratory conditions and confirm the existence of cardiac arrhythmias in well-trained BHD.

Adaptation, Physiological↗
PubMed2005

The World Anti-Doping Code 2003--consequences for physicians associated with elite athletes.

The purpose of the World Anti-Doping Code 2003 and the 2004 Prohibited List is to create a universal international standard to fight doping in competitive sports. The result of this is a whole series of changes for doctors with regard to their work with competitive athletes. The revised definition of doping now includes physicians in the group of persons who can fulfil the elements of a doping offence. Moreover, the mere possession of substances appearing on the Prohibited List represents a violation of anti-doping regulations. The 2004 Prohibited List includes several changes to the Olympic Movement List from 2003. Caffeine, for example, was removed from the list. Cannabinoids, on the other hand, are now prohibited in competition for all sports. The same is true for all forms of glucocorticosteroids. Therapeutic use exemptions in an abbreviated process are possible for the administration of glucocorticosteroids by non-systemic routes, as well as inhalative therapy with the beta-2-agonists formoterol, salbutamol, salmeterol, and termbutalin. In other cases, a therapeutic use exemption is possible using a standard application process. Further changes will become effective in the 2005 Prohibited List. In 2005, it is essential that beta-2-agonists are prohibited in and out of competition. HCG and LH are prohibited for all athletes. Dermatological preparations of glucocorticosteroids are no longer prohibited, and intravenous infusions will be a prohibited method in 2005, except as a legitimate acute medical treatment. In cases of violations of anti-doping regulations where it is permissible for the affected person to furnish proof of exoneration, the burden of proof is not higher than that required to prove the violation. The sanctions provided for in the World Anti-Doping Code follow a principle of rules and exceptions which at first glance seems difficult to understand. In the case of doping violations by physicians, the anti-doping code provides--as a general rule--for exclusion from sports associations for at least four years. Since several of the changes are questionable under constitutional aspects, it remains to be seen whether the World Anti-Doping Code 2003 will allow the achievement of a universal standard to combat doping.

Adrenergic beta-Agonists↗
PubMed2006

Antioxidant status and oxidative stress in professional rugby players: evolution throughout a season.

Physical training is known to increase the antioxidant defence system and reduce exercise-induced oxidative stress. However, intense physical aerobic and anaerobic training and competition such as those imposed on professional rugby players, can induce an increase of oxidative stress which can be implicated with the arrival of overtraining. The aim of this study was to test the effect of training and competition load on oxidative stress, antioxidant status, haematological, and cell damage markers in high-level rugby players during a competitive season. Blood samples were collected four times in one year. Oxidative stress (Rmax), antioxidant (vitamin E, uric acid, TAC, and lag phase), haematological (neutrophils and monocytes) and biochemical (CK and myoglobin) parameters, as well as training and competition load, and competition results were measured. Intense periods of training and competition (T1 and T4) induced a significant higher maximum rate of conjugated dienes oxidation (+67.2% in T1 and +40.6% in T4) compared to those observed at the reference time (T3). Those periods also induced an increase in uric acid (+6.9% and 3.2%), and inflammatory markers such as monocytes (+13.3% and 10.7%). On the other hand, vitamin E (-8.7% in T1) and lag phase (-23.0% and -14.7%) were lower during these periods showing a possible training-induced antioxidant down-regulation. The less intense period of training (T2) was accompanied by lower neutrophils (-8.5%), CK (-53.7%), and myoglobin (-16.2%) values. The results suggest that oxidative stress and antioxidant measurement are significant in the biological follow-up of athletes.

Adult↗
PubMed2006

The consequences of swim, cycle, and run performance on overall result in elite olympic distance triathlon.

This study examined the consequences of performance in swim, cycle, and run phases on overall race finish in an elite "draft legal" Olympic distance (OD) triathlon. The subjects were 24 male athletes grouped by rank order into the top 50 % (n = 12) and bottom 50 % (n = 12) of the race population. Swimming velocity (m x s (-1)), cycling speed (km x h (-1)), and running velocity (m x s (-1)) were measured at regular intervals using a global positioning system, chip timing system, and video analysis. Actual rank after each stage and overall was obtained from the race results and video analysis. The top 50 % athletes overall swam faster over the first 400 m of the swim phase (p > 0.05). Their swim ranking was lower (p < 0.01) than the bottom 50 % athletes after this stage. There were no significant differences in actual race position between the groups after the cycle. However, the bottom 50 % athletes after the swim stage cycled faster (p < 0.01) at 13.4 km of the cycle. Speed at 13.4 km of the cycle stage was inversely correlated (r = 0.60, p < 0.01) to running performance. Performance (rank and velocity) in the running stage was highly correlated with overall race result (r = 0.86 and - 0.53, respectively, both p > 0.01). It appears that inferior swimming performance can result in a tactic that involves greater work in the initial stages of the cycle stage of elite OD racing, and may influence subsequent running performance.

Analysis of Variance↗
PubMed2006

Stroke frequency and arm coordination in front crawl swimming.

This study aims to determine whether the arm coordination observed at different stroke rates (SR, number of arm stroke cycles per minute) differs according to the level of expertise. Thirteen non-expert (G(NE)) and 14 expert (G(E)) swimmers swam crawl five 25-m lengths at five stroke rate values: 35, 40, 45, 50, and 55 cycles.min(-1). Results show that the pattern of 45 % of G(NE) switched from the catch-up (a lag time is performed between the propulsive phases of the two arms) to the superposition coordination mode (both arms pushing simultaneously during a short period of the cycle) between 45 and 50 cycles.min(-1). Patterns of 62.4 % of G(E) switched in the same way between 50 and 55 cycles.min(-1). Significant differences in coordination patterns were found between G(NE) and G(E) only when SR was set at 45 cycles.min(-1). As non-expert swimmers seldom produce the superposition mode, but adopt this pattern when required to swim at high stroke rate values, it is suggested that this coordination mode is an emergent property of the movement.

Adult↗
PubMed2005

[Risk of injury in and adolescent and junior competitive karate].

Increasing professionalism in competitive karate has led to a specific injury pattern. The aim of our study was to investigate the injury pattern in junior competitive karate and to evaluate the prophylactic effect of fist padding. During the 4 (th) Junior World Championships of the World Karate Confederation (WKC) 2004 235 karate fights were observed and injury-related data were recorded. Fist padding was used in 183 fights, 52 fights were carried out without. In 22 % of all fights we saw an injury. Most of them were mild injuries of the head and face: 32 bruises of the face (13 with epistaxis), 7 facial lacerations and 3 concussions (mild brain injury). 14 fights were stopped due to an injury. Only in the category male 18 - 20 years a higher rate of injuries was seen without fist padding (shobu ippon) compared to shobu sanbon (with fist padding). The injury pattern of junior competitive karate is comparable to senior karate. Fist padding does not generally reduce the incidence or severity of injuries.

Adolescent↗
PubMed2006

Loss of motor control and/or loss of consciousness during breath-hold competitions.

Since the first official world championships in breath-hold diving (1996), a sport has developed where the athletes compete in various disciplines of breath-hold diving. One of the rules is that the diver should surface from a dive without showing any signs of hypoxia. Depending on the severity of hypoxia, a diver may suffer disqualifying signs such as loss of consciousness (LOC) or loss of motor control (LMC), the latter including signs such as confusion, affected postural control, spasms or speech problems. Data was collected from the results of the major international competitions following AIDA guidelines (Association International pour le Dévelopment de l'Apnée) in 1998, 2001-2004. The data was analyzed for frequency of LOC and LMC during constant weight diving and during static apnea. In constant weight diving, the diver swims down (and up) as deeply as possible along a vertically suspended rope (current record 105 m). In static apnea, the diver strives for maximum duration, floating motionless face down in a pool (current record 8.58 min). A total of 601 static apnea (SA) performances and 596 constant weight dives were judged in the six competitions. On average, 10 % of SA, and 11 % of CW performances were disqualified due to signs of hypoxia. For the competitions in 2002-2004, a distinction was made in the rules between LOC and LMC; of a total number of 355 SA performances, 1.1 % resulted in LOC, while 9.6 % resulted in LMC. For CW, the number was 344 with 6.1 % LOC and 6.1 % LMC. Despite the relatively high incidence of dramatic signs, it is noteworthy that there have been no reports of fatal accidents or permanent injuries from any of the above-mentioned competitions. This descriptive paper shows a relatively high incidence of disqualifications due to signs of hypoxia in breath-hold competitions 1998-2004.

Competitive Behavior↗
PubMed1994

Indices of training stress during competitive running and swimming seasons.

Eight male cross-country runners and five male swimmers were tested four times during their collegiate seasons. Each trial corresponded to a different training load. The runners' trials were conducted before the start of organized practice (RT1), after 3 wk of increased training (RT2), 3 wk prior to the conference championship (pre-taper, RT3), and 4 d after the conference championship (post-taper, RT4). The swimmers' trials were conducted after the first 9 wk of training (ST1), after completing 2 wk of hard training (ST2), after an additional 6 wk of training (pre-taper, ST3) and during a week following the conference championship (post-taper, ST4). Venous blood samples, heart rate (HR) and blood pressure (BP) were obtained after 15 min supine rest (0700 h). Serum was analyzed for cortisol (C), total testosterone (TT), free testosterone (FT), and creatine kinase (CK). Blood samples (lactate), HR and RPE were obtained during a fixed velocity run (75% preseason VO2max) and blood samples and RPE following a 365.8 m swim (90% preseason VO2max). The runners then completed a "performance run" to exhaustion (110% preseason VO2max) and the swimmers completed maximal 22.9 and 365.8 m swims. Serum CK, C, TT, FT, and the TT:C and FT:C ratios were not significantly different among trials for the runners. Serum TT and FT were significantly (P < 0.05) lower for the swimmers at ST2 (TT 16.7 +/- 2.5; FT 85.3 +/- 8.5) compared to ST1 (TT 30.3 +/- 2.8; FT 130.2 +/- 20.9) whereas, C, TT:C or FT:C were not significantly altered.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗
PubMed1992

The distribution of anaerobic energy in 1000 and 4000 metre cycling bouts.

In sprinting events of short duration, performance depends not only on the mean external power output and the frictional losses but also on the distribution of energy over the race. To investigate the optimal distribution of anaerobic energy during cycling the 1000 m time trial and the 4000 m pursuit, we simulated a power equation which contains expressions for the production of aerobic and anaerobic power, for frictional losses and for the rate of change of kinetic energy. Parameters for air- and rolling resistance were derived from the literature and the equations for aerobic and anaerobic power production were based on supra-maximal bicycle ergometer tests. Simulated lap and final times were compared to those realized by the best four athletes during the 1990 World Championships. The mean final times of these athletes of 64.1 s and 272.6 s for the 1000 m and 4000 m respectively were closely approximated by the simulated times of 63.7 s and 281.3 s. The simulations show that performance in the 1000 m race depends to a great extent on a large power output at the onset of the race. Moreover, it is demonstrated that this distance should be cycled in an all out fashion and not with a uniform velocity after the start despite the higher air frictional losses. For the 4000 m pursuit it appears to be more effective to perform a short but powerful start and then continue the race with a constant or only slightly decreasing power output.

Bicycling↗
PubMed1992

Exercise and neuromodulators: choline and acetylcholine in marathon runners.

Certain neurotransmitters (i.e., acetylcholine, catecholamines, and serotonin) are formed from dietary constituents (i.e., choline, tyrosine and tryptophan). Changing the consumption of these precursors alters release of their respective neurotransmitter products. The neurotransmitter acetylcholine is released from the neuromuscular junction and from brain. It is formed from choline, a common constituent in fish, liver, and eggs. Choline is also incorporated into cell membranes; membranes may likewise serve as an alternative choline source for acetylcholine synthesis. In trained athletes, running a 26 km marathon reduced plasma choline by approximately 40%, from 14.1 to 8.4 uM. Changes of similar magnitude have been shown to reduce acetylcholine release from the neuromuscular junction in vivo. Thus, the reductions in plasma choline associated with strenuous exercise may reduce acetylcholine release, and could thereby affect endurance or performance.

Acetylcholine↗
PubMed1992

Training at altitude in practice.

There can be little doubt that training at altitude is fundamental to preparing an athlete for competition at altitude. However the value of training at altitude for competition at sea level appears on the one hand to lack total acceptance amongst sports scientists; and on the other to hold some cloak of mystery for coaches who have yet to enjoy first hand experience. The fact is that very few endurance athletes will ignore the critical edge which altitude training affords. Each fraction of a percentage of performance advantage gained through methods which are within the rules of fair play in sport, may shift the balance between failure and achievement. Moreover, there is growing support for application of training at altitude for speed-related disciplines. This paper aims to demystify the subject by dealing with practical aspects of training at altitude. Such aspects include a checklist of what should and should not be done at altitude, when to use altitude relative to target competitions, and specific training examples.

Acclimatization↗
PubMed1991

Anxiety and intense running exercise in the presence and absence of interpersonal competition.

The purposes of this study were to evaluate the effects of intense running exercise in the presence and absence of interpersonal competition on both (a) pre-exercise anxiety levels and (b) alterations in anxiety as a consequence of the exercise. Seven females and 10 males performed a 5-mile run over the same outdoor course on two separate days. In one condition the subjects ran in a road-race in which intense exercise was combined with interpersonal competition. In the second condition, exercise of the same intensity (84% VO2max) and duration was completed, but interpersonal competition was absent. Cognitive (State-Trait Anxiety Inventory; STAI) and somatic (Body Awareness Scale; BAS) aspects of anxiety were measured 15 min before and after exercise as well as on a separate day under non-stressful, baseline conditions. A main effect for the Trials factor was found using repeated measures ANOVA [Condition (presence/absence of interpersonal competition) X Gender X Trials (baseline/pre-exercise/post-exercise)], and post-hoc analysis revealed that post-exercise state anxiety and body awareness levels were both reduced compared to pre-exercise baseline values. Condition and Gender main effects were not significant nor were any of the interaction effects. Pre-exercise STAI and BAS levels were found to be significantly (p less than .01) elevated above baseline values. However, while post-exercise STAI scores were significantly (p less than .01) below the baseline STAI level, the post-exercise BAS values did not fall below the corresponding baseline level.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Perception of effort in female and male competitive swimmers.

The primary purpose of this investigation was to compare 31 competitive female swimmers with 31 competitive male swimmers on their perceptual responses to submaximal swimming. A secondary purpose was to evaluate the relationship between heart rate (HR) and perceived exertion (RPE) in swimming. Each swimmer completed a 200-yd swim in his/her specialty stroke at 90% of the swimmer's current best time. Underwater and overhead pace lights were used to achieve an even pace during the swims, and HR was monitored by means of radiotelemetry. Ratings of overall and local perceived exertion were assessed immediately following each swim with Borg's 6-20 scale. ANOVA revealed no RPE differences across stroke classifications for the female or male swimmers, but local and overall RPE were lower (p less than 0.01) in the females. Mean HR, however, was significantly higher (p less than 0.05) for the female swimmers. Unlike research with other exercise modes, correlational analyses revealed that overall and local RPE were unrelated to HR (p greater than 0.05). Based on these findings, it is concluded that 1) female swimmers judged a paced swim to be less effortful than did male swimmers despite a greater objective strain in the females, and 2) HR was not correlated with perception of effort.

Adolescent↗
PubMed1991

Psychological aspects of staleness and dependence on exercise.

This article discusses the psychological symptoms of overtraining and the relationship between staleness and exercise dependence. Staleness may be prevented by monitoring the mood state of the individual so that, if necessary, appropriate action may be taken to taper the volume of training and maximize performance. The criterion for exercise dependence is difficult to define and some suggestions are made on clarifying the diagnosis and future research in this area.

Affect↗