Biomedical subjects

Barry A Spiering

Publications and source records attributed to Barry A Spiering.

22 records · Page 2Linked to original sources

PubMed2003

Bronchoconstriction during cross-country skiing: is there really a refractory period?

PURPOSE: The asthmatic airway responds to exercise by bronchodilation (BD) during and bronchoconstriction (BC) after exercise. A refractory period induced by an initial exercise challenge that provides protection against BC during a subsequent exercise bout has also been observed. However, no studies examining during-exercise response or refractoriness during long-duration field exercise by elite athletes have been performed. This study examined airway response and refractoriness during approximately 42-min cross-country ski time trial preceded by a 6- to 9-min 2.5-km high-intensity warm-up ski. METHODS: Eighteen elite athletes cross-country skied seven successive 2.5-km loops. Spirometry was performed pre- and at 5, 10, and 15 min post loop 1; loops 2-7 were treated as a race (XCR) with maneuvers performed within 20 s after loops 2-6 and serially for 15 min after lap 7. RESULTS: Nine of 18 subjects demonstrated a >or=10% fall from baseline in FEV(1) (EIB+): five after lap 1 and four during or after laps 2-7. FEV(1) for EIB+ athletes during XCR was not different from post lap 1 FEV. Only one EIB+ subject demonstrated significant refractoriness. Four EIB+ athletes had a less than 10% fall in FEV after the initial 2.5-km exercise challenge but developed EIB (>or=10% fall) during the subsequent 6 x 2.5 km XCR exercise challenge. FEF(25-75) falls mirrored FEV(1), but demonstrated greater BD during XCR. CONCLUSION: Bronchoconstriction occurs in athletes during prolonged exercise and may thus influence performance. Variability in bronchial hyperresponsiveness onset and the lack of significant refractoriness in our study cohort of athletes is consistent with an exercise bronchoconstrictive dysfunction that is different than frank asthma and is yet to be clearly defined.

Adolescent↗

PubMed2003

Effect of muscle oxygenation during resistance exercise on anabolic hormone response.

PURPOSE: The mechanisms that underlie the affect of acute program variables on muscle growth and strength development for strength/power athletes have been of great interest. This investigation examined the affects of two different resistance exercise protocols on muscle oxygenation, and the anabolic hormonal response to such exercise. METHODS: Eleven experienced resistance-trained male athletes performed four sets of the squat exercise using either a low-intensity, high-volume (LI; 15 repetitions at 60% one-repetition maximum [1-RM]) or high-intensity, low-volume (HI; 4 repetitions at 90% 1-RM) load. Venous blood samples were obtained before (Pre), immediate (IP), 20- (20P), and 40-min (40P) postexercise. Continuous-wave near-infrared spectroscopy was used to measure oxygen desaturation during exercise. RESULTS: No differences in muscle deoxygenation were seen between LI and HI. However, time-dependent postexercise reoxygenation was significantly different between the two exercise sessions (35.3 +/- 17.4 s vs 24.5 +/- 14.3 s in LI and HI, respectively). Testosterone and growth hormone (GH) concentrations were significantly elevated from Pre at IP, 20P, and 40P in both LI and HI. GH concentrations were higher (P<0.05) for LI than at HI at 20P and 40P. CONCLUSION: Muscle oxygen recovery kinetics appeared to be influenced by differences in the intensity and volume of exercise, and delayed reoxygenation appears to affect the GH response to exercise.

Adult↗

PubMed2003

Inspiratory stridor in elite athletes.

STUDY OBJECTIVES: Diagnosis and medical intervention for exercise-induced bronchospasm (EIB) are often based on self-reported symptoms, without spirometric confirmation. Inspiratory stridor (IS), a symptom of vocal cord dysfunction (VCD), is frequently mistaken for EIB wheeze. Athletes with exercise IS that spontaneously resolves on activity cessation are suspect for VCD and may not have EIB. This study estimated IS prevalence in elite athletes and determined its relationship to EIB. SUBJECTS/METHODS: Three hundred seventy athletes (174 female and 196 male subjects) provided a medical history, and underwent spirometry before and after exercise challenge. Exercise challenges were conducted in cold, dry ambient conditions. EIB positive (EIB +) was defined as a > or = 10% postexercise fall in FEV(1). Athletes were monitored for IS during exercise; 78.4% of the athletes in this study (n = 290) were tested on multiple occasions. RESULTS: EIB was identified in 30% of 370 athletes tested (58 female and 53 male subjects). IS was observed in 5.1% (18 female and 1 male subjects) during exercise and spontaneously resolved in these subjects within 5 min after exercise cessation. Ten IS-positive (IS +) athletes (52.6%) were EIB +, and 8 of these athletes had a previous EIB diagnosis; however, beta(2)-agonist treatment resolved IS in only 2 subjects. Eight of nine IS +/EIB-negative (EIB -) athletes had a previous EIB diagnosis; seven subjects received beta(2)-agonist treatment with no IS resolution. Resting spirometric measurements did not distinguish IS, but postexercise mid-flow (FEF(50)/FIF(50)) ratio > 1.5 was more frequent (33%, p < 0.05) among IS + athletes. The FEF(50)/FIF(50) ratio was higher for IS +/EIB + athletes than for IS -/EIB + athletes (1.97 +/- 1.69 vs 0.81 +/- 0.39, p < 0.05). The postexercise fall in FVC was greater (p < 0.05) for IS +/EIB - athletes (9.2 +/- 5.0%) than for IS-negative (IS -) /EIB - athletes (5.3 +/- 4.3%). No difference in postexercise FEV(1) was identified between IS + and IS - athletes (within EIB + or EIB - groups). CONCLUSIONS: Five percent of athletes were IS +, with EIB comorbidity observed in 53% of these subjects. Misdiagnosis of IS as EIB is common. The lack of a beta(2)-agonist response in combination with postexercise serial spirometry can be useful in excluding solitary IS and confirming EIB diagnosis.

Adolescent↗

PubMed2003

Evaluation of cardiovascular demands of game play and practice in women's ice hockey.

Preparation for the physical demands of competition often involves game simulation during practice. This paradigm is thought to promote physiological adaptations that enhance maximal performance. However, a mismatch between practice intensity and actual competition intensity may not provide adequate training to achieve optimal game-play fitness. The purpose of this study was to evaluate the effectiveness of practice in meeting the cardiovascular demands of a women's ice hockey game. Heart rate (HR) data from 11 U.S. National Women's Ice Hockey team members were collected (5-second intervals) during a game and a typical practice session. Data was normalized to individual HRmax determined during Vo(2)max testing. Working time was defined as a game shift or practice-working interval. Mean working HR was greater during the game than the practice, 90 +/- 2% and 76 +/- 3% of HRmax, respectively (p < 0.05). Mean percent session time (game or practice) >90% HRmax was also longer during the game than the practice, 10.5 +/- 4.1% and 5.6 +/- 3.5% (p < 0.05), respectively. Mean session HR, percent time >80% HRmax, and mean resting HR were not different between game and practice (68 +/- 7% vs. 69 +/- 5%, 23.2 +/- 5.3% vs. 26.1 +/- 9.2%, and 59 +/- 8% vs. 56 +/- 5%, respectively). Elite women hockey players experience significantly greater cardiovascular load during game play than during practice. This mismatch in cardiovascular demand may prevent players from achieving "game shape," thus affecting competition play.

Adult↗