The authors examined whether changes in heart-rate (HR) variability (HRV) could consistently track adaptation to training and race performance during a 32-wk competitive season. An elite male long-course triathlete recorded resting HR (RHR) each morning, and vagal-related indices of HRV (natural logarithm of the square root of mean squared differences of successive R−R intervals [ln rMSSD] and the ratio of ln rMSSD to R−R interval length [ln rMSSD:RR]) were assessed. Daily training load was quantified using a power meter and wrist-top GPS device. Trends in HRV indices and training load were examined by calculating standardized differences (ES). The following trends in week-to-week changes were consistently observed: (1) When the triathlete was coping with a training block, RHR decreased (ES −0.38 [90% confidence limits −0.05;−0.72]) and ln rMSSD increased (+0.36 [0.71;0.00]). (2) When the triathlete was not coping, RHR increased (+0.65 [1.29;0.00]) and ln rMSSD decreased (−0.60 [0.00;−1.20]). (3) Optimal competition performance was associated with moderate decreases in ln rMSSD (−0.86 [−0.76;−0.95]) and ln rMSSD:RR (−0.90 [−0.60;−1.20]) in the week before competition. (4) Suboptimal competition performance was associated with small decreases in ln rMSSD (−0.25 [−0.76;−0.95]) and trivial changes in ln rMSSD:RR (−0.04 [0.50;−0.57]) in the week before competition. To conclude, in this triathlete, a decrease in RHR concurrent with increased ln rMSSD compared with the previous week consistently appears indicative of positive training adaptation during a training block. A simultaneous reduction in ln rMSSD and ln rMSSD:RR during the final week preceding competition appears consistently indicative of optimal performance.
Jamie Stanley, Shaun D’Auria and Martin Buchheit
Henry C. Lukaski, William W. Bolonchuk, Leslie M. Klevay, David B. Milne and Harold H. Sandstead
In a pilot study, performance measures and mineral metabolism were assessed in 3 male endurance cyclists who consumed isoenergetic, isonitrogenous diets for 28-day periods in a randomized, crossover design in which dietary carbohydrate, polyunsaturated, or saturated fat contributed about 50% of daily energy intake. Peak aerobic capacity [62 ml/(kg · min)] was unaffected by diet. Endurance capacity at 70–75% peak aerobic capacity decreased with the polyunsaturated fat diet. Copper retention tended to be positive only with saturated fat. Less iron and zinc were retained (intake – losses), and fecal losses of these minerals increased with the polyunsaturated fat. Blood biochemical measures of trace element nutritional status were unaffected by diet, except serum ferritin, which tended to decrease during consumption of the polyunsaturated fat diet. These preliminary results suggest that diets high in polyunsaturated fat, particularly linoleic acid, impair absorption and utilization of iron and zinc, and possibly magnesium, and may reduce endurance performance.
Michael J. Duncan
A 10-week plyometrics-based intervention was carried out with a county-level hurler during preseason preparation. The intervention resulted in a number of physiological changes specific to hurling performance. Most notably, it enabled the athlete to complete repeated sprints with less decrement in performance compared with baseline scores.
Paolo Menaspà, Ermanno Rampinini, Lara Tonetti and Andrea Bosio
To describe the physical fitness of a top-level lower limb amputee (LLA) cyclist and paracycling time-trial (TT) race demands.
The 40-y-old male unilateral transfemoral amputee TT World Champion was tested in a laboratory for peak oxygen uptake (VO2peak), ventilatory threshold (VT2), power output (PO), and hemoglobin mass (Hb-mass). Moreover, several measures (eg, PO, heart rate [HR], cadence) were collected during 4 international TT competitions in the same season. The races’ intensity was evaluated as time spent below, at, or above VT2.
The cyclist (1.73 m, 55.0 kg) had a VO2peak of 3.372 L/min (61.3 mL · kg−1 · min−1). The laboratory peak PO was 315 W (5.7 W/kg). The maximal HR was 208 beats/min, and his Hb-mass was 744 g (13.5 g/kg). The TTs were meanly 18 ± 4.5 km in length, and the mean PO was 248 ± 8 W with a cadence of 92 ± 1 rpm. During the TTs, the cyclist spent 23% ± 9% of total time at VT2, 59% ± 10% below, and 18% ± 5% above this intensity.
The subject’s relative VO2peak is higher than previously published data on LLA, and surprisingly it is even higher than “good” ACSM normative data for nondisabled people. The intensity of the races was found to be similar to cycling TTs of the same duration in elite female cyclists. These results might be useful to develop specific training schedules and enhance performance of LLA cyclists.
Martin D. Hoffman and Thomas M. Myers
Symptomatic exercise-associated hyponatremia (EAH) is known to be a potential complication from overhydration during exercise, but there remains a general belief that sodium supplementation will prevent EAH. We present a case in which a runner with a prior history of EAH consulted a sports nutritionist who advised him to consume considerable supplemental sodium, which did not prevent him from developing symptomatic EAH during a subsequent long run. Emergency medical services were requested for this runner shortly after he finished a 17-hr, 72-km run and hike in Grand Canyon National Park during which he reported having consumed 9.2–10.6 L of water and >6,500 mg of sodium. First responders determined his serum sodium concentration with point-of-care testing was 122 mEq/L. His hyponatremia was documented to have improved from field treatment with an oral hypertonic solution of 800 mg of sodium in 200 ml of water, and it improved further after significant aquaresis despite in-hospital treatment with isotonic fluids (lactated Ringer’s). He was discharged about 5 hr after admission in good condition. This case demonstrates that while oral sodium supplementation does not necessarily prevent symptomatic EAH associated with overhydration, early recognition and field management with oral hypertonic saline in combination with fluid restriction can be effective treatment for mild EAH. There continues to be a lack of universal understanding of the underlying pathophysiology and appropriate hospital management of EAH.
Andrew Renfree, Graham J. Mytton, Sabrina Skorski and Alan St Clair Gibson
To identify tactical factors associated with progression from preliminary rounds in middle-distance running events at an international championship.
Results from the 2012 Olympic Games were used to access final and intermediate positions, finishing times, and season-best (SB) times for competitors in men’s and women’s 800-m and 1500-m events (fifteen 800-m races and ten 1500-m races). Finishing times were calculated as %SB, and Pearson product–moment correlations were used to assess relationships between intermediate and finishing positions. Probability (P) of qualification to the next round was calculated for athletes in each available intermediate position.
There were no significant differences in finishing times relative to SB between qualifiers and nonqualifiers. In the 800-m, correlation coefficients between intermediate and final positions were r = .61 and r = .84 at 400 m and 600 m, respectively, whereas in the 1500-m, correlations were r = .35, r = .43, r = .55, and r = .71 at 400 m, 800 m, 1000 m, and 1200 m, respectively. In both events, probability of qualification decreased with position at all intermediate distances. At all points, those already in qualifying positions were more likely to qualify for the next round.
The data demonstrate that tactical positioning at intermediate points in qualifying rounds of middle-distance races is a strong determinant of qualification. In 800-m races it is important to be in a qualifying position by 400 m. In the 1500-m event, although more changes in position are apparent, position at intermediate distances is still strongly related to successful qualification.
John Kenny, SarahJane Cullen and Giles D. Warrington
“Ice-mile” swimming presents significant physiological challenges and potential safety issues, but few data are available. This study examined deep body temperature (BT), respiratory rate (RR), and swim performance in 2 swimmers completing an ice-mile swim of 1 mile (1600 m) in water less than 5°C.
Two male cold-water-habituated swimmers completed a 1-mile lake swim in 3.9°C water. For comparative purposes, they completed an indoor 1-mile swim in 28.1°C water. The Equivital physiological monitoring system was used to record BT and RR before, during, and after each swim. Total time to complete the swims and 400-m splits were recorded.
One swimmer became hypothermic after 27 min while swimming, reaching BT of 33.7°C at swim’s end. On exiting the water the swimmers experienced large BT after-drops of –3.6°C and –2.4°C, reaching low points of 33.2°C and 31.3°C 38 and 23 min postswim, respectively. Respiratory rate and swim pace decreased over the course of the ice-mile swim for both swimmers. Swim pace for 1 swimmer declined sharply in the final 400-m lap of the ice mile when he was hypothermic. Both swimmers remained hypothermic 60 min postswim (34.2°C and 33.4°C).
Ice-mile swimmers may become hypothermic while swimming, and the postswim BT after drop may expose them to dangerous levels of hypothermia. Pace and RR should be monitored as proxies for a swimmer’s physiological state. Postswim recovery should also be monitored for hypothermia for at least 1 h.
Jessie M. Wall, Janelle L. Kwee, Marvin J. McDonald and Richard A. Bradshaw
This study was the first to explore the treatment effects of observed and experiential integration (OEI) therapy for the salient psychological barriers to performance experienced by athletes. The hermeneutic single case efficacy design was used to explore the relationship between OEI therapy and athlete psychological functioning. The participant was a student-athlete who met the criteria for the performance dysfunction (multilevel classification system of Sport psychology) category, which indicates that subclinical issues were present. After five phases of data collection, a rich case record was compiled and referenced to develop skeptic and affirmative briefs and corresponding rebuttals by two research teams of three experts (OEI clinician, non-OEI clinician, and sport expert). Three independent judges adjudicated the cases and unanimously concluded that the client changed considerably to substantially and that OEI, the therapeutic relationship, and client expectancy were active variables in the change process.
Motohide Miyahara and Alena Wafer
The teaching process and outcome in a skill theme program and a movement concepts program were described and analyzed in seven children with developmental coordination disorder. It was hypothesized that the skill theme program would improve targeted skills and perceived physical competence, whereas the movement concepts program would improve self-esteem and creativity. The seven children were taught individually by the same student teachers twice a week for a period of five weeks in one of the teaching methods. After a vacation, the teachers changed their teaching strategies and taught the same children using the alternative method. Although the hypothesis was generally supported, the children’s response to and progress in the programs varied. Possible factors influencing the variation were discussed.
Charles A. Maher
This article reflects a response to the case of a freshman student-athlete lacrosse player who was in the process of transitioning into a Division I environment. Within the context of the case response, guidelines were provided for assessment of the student-athlete at four separate, yet interrelated levels of psychological development. These levels were: as a person; as a student-athlete who exists in a high-risk environment; as a teammate; and as a performer in the sport of lacrosse. Relatedly, it was suggested how the strengths and needs of this individual could be assessed and how resulting needs assessment information could be used in the design of an individual plan for the student-athlete. As such, it was suggested that the individual plan would most likely center on helping the individual to become increasingly aware of herself as a person and performer, to offer guidance in adhering to her physical rehabilitation, and to develop a routine for her daily preparation and for monitoring her practice and game performances. The case response concludes with a description of a framework for determining the student-athlete’s readiness for engaging in the plan and its activities.