ABSTRACT
The purpose of this study was to assess the contribution of SCUBA to the pulmonary effects of diving to 4.5 meters depth in healthy subjects using a randomized crossover control condition. Ten healthy divers performed two 60-minute 'dives' using SCUBA in a swimming pool. The non-immersed 1 ATA SCUBA control exposure took place at ambient pressure in the laboratory. Thirty minutes prior to, and 30 and 90 minutes post-exposure, FVC (forced vital capacity), FEV1.0 (forced expired volume), peak expiratory flow rate (PEFR), diffusing capacity (DL(co)), heart rate (HR) and temperature were measured. No significant differences were noted in HR, temperature or spirometry between the two conditions. A significant reduction in diffusing capacity occurred at 30 and 90 minutes after the pool dive (9.3% and 15.1%, respectively, p < 0.05). There was no concordant change in DL(co) following the non-immersed 1 ATA SCUBA control. Thus, a pool dive to 4.5 meters for 60 minutes causes a decrease in DL(co), without a change in spirometry, while breathing from SCUBA equipment without immersion causes no significant change in lung function.
Subject(s)
Diving/physiology , Pulmonary Diffusing Capacity/physiology , Adult , Analysis of Variance , Cross-Over Studies , Female , Forced Expiratory Volume , Humans , Male , Peak Expiratory Flow Rate , Spirometry , Time Factors , Ventilators, Mechanical , Vital CapacityABSTRACT
OBJECTIVES: To determine the effect of prophylactic treatment with an inhaled bronchodilator and anti-inflammatory on arterial saturation (SaO2) in trained non-asthmatic male athletes with exercise induced arterial hypoxaemia (EIAH). METHODS: Nine male athletes (mean (SD) age 26.3 (6.7) years, height 182.6 (7.9) cm, weight 79.3 (10.5) kg, VO2MAX 62.3 (6.3) ml/kg/min, SaO2MIN 92.5 (1.1)%) with no history of asthma were tested in two experimental conditions. A combination of a therapeutic dose of salbutamol and fluticasone or an inert placebo was administered in a randomised crossover design for seven days before maximal cycling exercise. Oxygen consumption (VO2), ventilation (VE), heart rate (HR), power output, and SaO2 were monitored during the exercise tests. RESULTS: There were no significant differences between the drug (D) and placebo (P) conditions for minimal SaO2 (D = 93.6 (1.4), P = 93.0 (1.1)%; p = 0.93) VO2MAX (D = 61.5 (7.2), P = 61.9 (6.3) ml/kg/min; p = 0.91), peak power (D = 444.4 (48.3), P = 449.4 (43.9) W; p = 0.90), peak VE (D = 147.8 (19.1), P = 149.2 (15.5) litres/min; p = 0.82), or peak heart rate (D = 182.3 (10.0), P = 180.8 (5.5) beats/min; p = 0.76). CONCLUSIONS: A therapeutic dose of salbutamol and fluticasone did not attenuate EIAH during maximal cycling in a group of trained male non-asthmatic athletes.
Subject(s)
Albuterol/administration & dosage , Androstadienes/administration & dosage , Bronchitis/complications , Bronchodilator Agents/administration & dosage , Hypoxia/drug therapy , Sports/physiology , Administration, Inhalation , Adult , Cross-Over Studies , Double-Blind Method , Drug Therapy, Combination , Exercise Test/methods , Fluticasone , Heart Rate/drug effects , Heart Rate/physiology , Humans , Hypoxia/etiology , Male , Oxygen Consumption/drug effects , Oxygen Consumption/physiologyABSTRACT
OBJECTIVE: To examine venous partial pressure of oxygen (PvO(2)), transcutaneous oxygen tension (tcPO(2)), and VO(2)MAX in a normobaric environment after a single hyperbaric oxygen (HBO(2)) treatment. METHODS: This was a prospective study of conditions after the intervention compared with baseline. The participants were 10 moderately trained (VO(2)MAX = 57.6 ml/kg/min) men. Two HBO(2) treatments consisting of breathing 95% oxygen at 2.5 atmospheres absolute (ATA) for 90 minutes were administered on non-consecutive days. Baseline testing included measures of VO(2)MAX, tcPO(2), and anthropometry. At 6.0 (1.0) minutes after the first HBO(2) treatment, a VO(2)MAX test was performed. After the second HBO(2) treatment, leg and chest tcPO(2) and PvO(2) were monitored for 60 minutes. RESULTS: VO(2)MAX, running time, and peak blood lactate were not altered after the HBO(2) treatment. Leg tcPO(2) was lower (p = 0.003) and chest tcPO(2) was unchanged after the HBO(2) treatment compared with baseline values. PvO(2) was significantly (p<0.001) lower in the first three minutes after treatment than subsequent values, but no other differences were found. CONCLUSIONS: A single HBO(2) treatment at 2.5 ATA for 90 minutes does not raise PvO(2), tcPO(2), or VO(2)MAX in a normobaric, normoxic environment.
