[[alternative]]Impact of Recreational Diving on Cardiovascular and Respiratory System

[[abstract]]背景：近來海洋運動風氣興盛，從事休閒潛水人口逐年增加。在休閒潛水員養成培育期，課程多著重於潛水及呼吸技巧訓練，然而休閒運動者最為重視的健康資訊卻寥寥無幾，缺乏充足資料文獻。目的：為瞭解水肺潛水對呼吸、心血管及自律神經系統的影響。方法：本研究於臨海潛水地點，招募自願且具備合格證照男性，依潛水資歷區分為學員組及教練組，每組各16人，觀察從事單次潛水活動前、後之肺功能、最大呼吸肌力及血管彈力、心跳變異率與自律神經平衡狀況之差異，評估休閒潛水活動對健康的影響。結果：本研究發現潛水前、後二組間潮氣量達顯著差異 (F=9.18，P= .01)，相較於潛水前，經常從事潛水活動的教練組，潛水後潮氣容積顯著增高（潛水前vs後：1.19 ± 0.7 L vs 1.70 ± 0.5 L，p= .03），心跳率顯著減低（潛水前vs後：90.4 ± 17 bpm vs 84.7 ± 14 bpm，p= .05），且二組間之最大吸氣肌力達顯著差異 (F=5.68，P= .02)，無論潛水前或潛水後，教練組均顯著高於學員組 (p≦ .05）；另外，短期於假日從事休閒潛水的學員組，潛水後極為顯著的減低最大吸氣壓（潛水前vs後：83.6 ± 20 cmH2O vs 66.4 ± 18 cmH2O，p= .01），以及最大呼氣壓（潛水前vs後：69.1 ± 22 cmH2O vs 55.9 ± 18 cmH2O，p= .03）、以及平均呼氣量（潛水前vs後：56.0 ± 18 cmH2O vs 43.5 ± 14 cmH2O，p= .01）；最值得關注的是：二組人員潛水後血管狀況皆顯著優於潛水前 (p≦ .05)，血管老化指數二組的組別間具有顯著差異 (F=5.32，P= .03)，學員組潛水後顯著優於潛水前（潛水前vs後：-104 ± 33 a.u. vs -122 ± 29 a.u.，p= .03），並極為顯著的優於教練組的潛水後平均值（學員組vs教練組：-122 ± 29 a.u. vs -82 ± 49 a.u.，p= .01）；然而在自律神經方面，無論是交感或副交感神經活性，本研究皆未發現顯著差異。結論：休閒潛水雖然有利於立即短期改善心血管狀況，惟其健康促進效果短暫，無累積或遞延效應。此外，短期於休閒時從事水肺潛水運動，可能造成呼吸肌疲勞；然而長期、經常的訓練，有益於增強呼吸肌力與耐力，改善心肺的適應與調節能力。[[abstract]]Background: While cultivating recreational divers, most courses focus on diving and breathing skills training, yet little information on health which leisure exercisers value the most can be found. Purpose: To understand the effects of scuba diving on respiratory, cardiovascular and autonomic nervous systems. Methods: This study recruited volunteers with qualified certificates in the coastal diving area, and divided them into student group (SG) and coaching group (CG) accordingly, 16 persons for each group. Observe the differences in lung function, maximum respiratory muscle strength and vascular elasticity, heart rate variability and autonomic nerve balance before and after a single dive activity to assess the health effects. Results: That it differed greatly in tidal volume between both groups before and after diving (F= 9.18, P= .01). Compared with before diving, the CG who dive frequently increased the tidal volume (pre vs. post: 1.19 ± 0.7 L vs 1.70 ± 0.5 L, p= .03) and decreased heart rate significantly (pre vs. post: 90.4 ± 17 bpm vs 84.7 ± 14 bpm, p= .05) after diving. PImax of both groups differed a lot (F= 5.68, P= .02); CG’s was higher than SG’s (p≦ .05) before or after diving. Besides, the SG who are short-term recreational divers reduced much of the PImax (pre vs. post: 83.6 ± 20 cmH2O vs 66.4 ± 18 cmH2O，p= .01) and PEmax (pre vs. post: 69.1 ± 22 cmH2O vs 55.9 ± 18 cmH2O，p= .03) after diving, as well as the average expiratory volume (pre vs. post: 56.0 ± 18 cmH2O vs 43.5 ± 14 cmH2O，p= .01). It is noteworthy that the vascular status of both groups after diving is much better than before diving (p≦ .05). Both groups differed a lot in the vascular aging index (F=5.32, P=.03); the SG’s index after diving was much better than that before diving (pre vs. post: -104 ± 33 a.u. vs -122 ± 29 a.u., p= .03), and also much better than CG’s average value after CG dived (SG vs CG: -122 ± 29 a.u. vs -82 ± 49 a.u., p=.01). Conclusion: Although recreational diving is beneficial to improve cardiovascular status shortly and briefly, the effect on health is transient and can’t be deferred. Moreover, short-term scuba diving during leisure time may cause respiratory muscle fatigue; however, long-term and regular training to dive is beneficial to enhance respiratory muscle strength and endurance, and improve cardiopulmonary adaptation and adjustment