浸水による死亡と,冷たい水中の水泳能力の低下
1Department of Sport and Exercise Science, University of Portsmouth, UK. michael.tipton@port.ac.uk
Lancet (London, England)
|August 31, 1999
まとめ
冷水浸水は泳ぎ能力を低下させ,泳ぎに失敗し,溺れるリスクにつながります. 重度の低体温症だけでなく,早期のパフォーマンスの低下が,冷水事故の主要な危険です.
科学分野:
- 生理学 生理学とは
- 環境医学 環境医学
- スポーツ科学 スポーツ科学
背景:
- 一般的な低体温 (低体温<35°C) は,浸水による死亡と関連しています.
- しかし,急速な溺死は,他の要因が関与していることを示唆しています.
- この研究では,冷たい水中の水泳能力の変化を調査しています.
研究 の 目的:
- 寒い水が泳ぎのパフォーマンスにどのように影響するか調べるために.
- これらの変化が水泳不全や溺死につながるかどうかを判断する.
主な方法:
- 10人のボランティアは,25°C,18°C,および10°Cの温度で90分間,を泳いで泳ぎました.
- 測定には,酸素消費量,直腸温度,泳ぎ速度,角度,脳卒中率,長さなどが含まれていた.
- 泳ぎの失敗は,足が川の底から離れないようにすることができないこととして定義された.
主要な成果:
- 寒い水域で90分を泳いだ人は少なく,10°Cで5分から10分まで泳いだ人は少なくなった.
- 10°Cの水中で,1人の水泳選手は61分後に失敗し,4人は失敗寸前 (35°Cの直腸温度) で撤退した.
- 寒い水は,泳ぎの効率と泳ぎの長さを著しく低下させ,同時に泳ぎの速さと泳ぎの角度を増加させ,泳ぎの失敗が迫っていることを示した.
結論:
- 性能の低下と最初の心呼吸器反応は,冷水浸水における主要な危険です.
- 治療は,重度の低体温症ではなく,溺れ寸前の症状に焦点を当てなければならない.
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