運動後恢復期心臟代償反應與心肺健康有重要的關係，而游泳運動受到姿勢與環境的影響，可能引發與陸上運動不同的心臟代償生理反應。本研究目的為探討單次不同強度游泳運動對成年健康男女性運動後心臟代償現象的影響。受試者為8位成年健康男性（年齡：50.1 ± 3.1歲），及9位成年健康女性（年齡：53.9± 2.2歲）。依平衡次序方式進行三次的試驗；分別為30分鐘低強度（40% HRR, LE組）、中強度（70%HRR, ME組）游泳運動試驗及控制組（C組），並於試驗後第1、2、3、4、12及24小時觀察心臟功能參數（心跳率、每跳輸出量、心輸出量、左心室收縮時距、左心室壓力改變速率）。所得數據以混合設計三因子（性別 × 試驗 × 時間）變異數分析心臟功能參數。研究結果發現：每跳輸出量、左心室收縮時距、左心室壓力改變速率交互作用皆未達顯著。心跳率之組別與時間交互作用達顯著，單純主要效果分析運動後1小時，ME組 (82.2 ± 2.8 beats/min) 顯著高於LE組 (75.8 ± 2.3 beats/min)，兩組皆顯著高於C組（66.0 ± 1.8 beats/min）。運動後2小時，僅ME組顯著高於C組，運動後3、4小時ME組及LE組皆顯著高於C組。心輸出量之組別主要效果達顯著，ME組（4.6 ± 0.2 L/min）與LE組（4.5 ± 0.2 L/min）皆顯著高於C組（4.2 ± 0.2 L/min）。本研究結論：無規律運動習慣之中老年人從事單次30分鐘低或中強度游泳運動後恢復期，仍存在心輸出量因運動強度增加而上升的心臟代償現象，此現象主要是透過較高的心跳率而達成，且持續至運動後4 小時，同時此現象並無性別差異存在。

Post-exercise cardiac compensation is closely associated with cardiovascular health. Swimming exercise could elicit different post-exercise physiological responses compared to land-based exercise due to the environment and posture differences. The purpose of this study was to examine the effect of swimming exercise at two different intensities on post-exercise cardiac compensation in healthy middle-aged adults. Eight male (50.1 ± 3.1 yr) and 9 female (53.9 ± 2.2 yr) subjects were recruited for this study. Each subject completed an initial graded exercise test to determine individual maximal heart rate (HRmax) followed by a 30-min swimming exercise at low (40% HRR, LE), moderate (70% HRR, ME) intensities, and a sham control (CON) by using counter-balanced design. Hemodynamic variables were obtained at 1, 2, 3, 4, 12, and 24-h after exercise by using a 24-h ambulatory blood pressure monitor. Three-way analysis of variance (ANOVA) was used to assess the differences, main effects and interaction (gender × intensity × time) between controlled variables. We found no significant difference in stroke volume (SV), left ventricular ejection time (LV ejection time) and LV dp/dt Max after LE and ME. However, heart rate was significantly increased one hour after exercise in ME compared to LE (82.2 ± 2.8 vs. 75.8 ± 2.3 beats/ min), and both ME and LE showed higher than CON (66 ± 1.8 beats/min). The main effect on cardiac output was reached significantly higher in both ME (4.6 ± 0.2 L/min) and LE (4.5 ± 0.2 L/min) than CON (4.2 ± 0.2 L/min). Our findings conclude that cardiac compensation was still observed during 4-h recovery after 30-min swimming exercise at 40% HRR as well as 70% HRR without any gender difference.