海水フローティングの心身のリラクセーション効果に関する無作為割付比較試験  [in Japanese] A Randomized Controlled Trial of the Effect of Seawater Floating on Physical and Mental Relaxation  [in Japanese]

海洋療法は主に海水の浮力抵抗,粘性や成分特性,海にまつわる素材を生かした施術により治療効果やリラクセーションを図る代替療法であるが,その科学的根拠は十分ではない.本研究では,海水を用いたリラクセーションプログラムの1つであるフローティングの効果について,心臓自律神経系活動,精神特異的ストレスマーカー唾液中クロモグラニンA(CgA),心理的評価STAIを用い無作為割付クロスオーバー比較試験を採用して検討した.その結果,海水フローティング群のみにセッション終了後CgAは有意に減少し,STAIによる状態不安得点では両群ともに有意な減少が認められ,介入後の群間比較では海水フローティング群により大きな減少が認められた.一方,得られたリラクセーション効果が海水特性によるものかは本研究では明らかにされず,今後さらなる検討が必要と考えられた.

Background: Thalassotherapy is an alternative therapy that aims at relaxation and therapeutic effects through practices mainly utilizing buoyancy, resistance, viscosity and component characteristic of seawater, and materials related to the sea. However, there are not enough scientific evidences to prove its effectiveness. In this study, therefore, a randomized, crossover-controlled trial was conducted to examine the effect of seawater floating, which is one of relaxation programs in the thalassotherapy, monitoring cardiac and autonomic nervous system activities, and salivary chromogranin A (CgA), which is a mentality-specific stress marker, and psychological evaluation with State-Trait Anxiety Inventory (STAI). Subjects: Subjects included 18 adult males and females who had no health problem, such as skin, cardiovascular, or autonomic disorders. Methods: Subjects were randomly assigned into two groups, a seawater floating-group, and an onshore supine-group, and subjected both sessions at an interval of two days. Kraepelin test was carried out as a given amount of mental workload before the intervention. Heart rate, high-frequency component of cardiac and autonomic nervous system activities, concentration of salivary CgA and STAI score were compared between before and after the intervention. Results: A significant decrease in CgA after the session was observed only in the seawater floating-group. The state anxiety score of STAI indicated a significant decrease in both groups. The decrease was significantly larger in the seawater floating-group. Conclusion: We could not reveal whether or not the relaxation given by seawater floating was due to the characteristic of seawater. Further studies are needed to clarify the effect of seawater floating on relief of stress and on relaxation.