| 摘要: | 目的： 以電子心力測量法 (非侵入性血液動力監視儀) 探討24小時超級馬拉松於精英跑者中心臟功能參數量值與運動成績表現間的關係。
方法：這是一項前瞻性的研究，其中參與研究的20位超馬選手完成了在400米的跑道上24小時持續跑步。於比賽前一天即紀錄與監測其心臟功能的測量參數，接著賽後立即測量以及比賽後24小時，總共施行三次的測量。
所有參與研究的超馬運動員，依據所得到變數資料，分組做研究數據的討論，變數分類包括： 1.）有無接受靜脈輸液的介入治療。 2.) 跑步的總距離成績是否超過200公里。 3.）體重流失的變化是否大於3％。4.）血壓下降是否超過10％等四項研究議題討論。並於四項研究議題中會分析超馬運動員心臟疲勞期與恢復期的心臟功能參數變化，以評估心臟功能和運動成績表現。
結果：在分組成四項研究議題組別討論之前，所有受試的超馬運動員其心臟功能參數量值在心臟疲勞階段顯示左心室射血期下降（289.7±29.4與257.6±31.3毫秒，P <0.002），心輸出量的上升變化 （4.3±1.0與5.4±1.2L /分鐘，P = 0.007）以及超馬運動員在躺姿、坐姿和站姿的心跳速率加速變化（64.2±10.7與81.5±13.6 B P <0.001;66.1±8.5與86.2±14.3 BPM，P <0.001;73.2±10.9與92.8±13.2BPM，P <0.001）。身體重量減輕的監測所得數據（59.2±6.1與57.7±5.9公斤，P <0.001）。
所有受試者於恢復期時皆能呈現回到基準值的心臟功能測量值和體重數據。四項研究議題討論時雖然在統計上並非顯著，但當在個別地細分每一組時，其中輸液治療議題分組的運動員中沒有接受輸液治療的非介入組中可看出其擁有更資深的馬拉松跑步經驗（8.3±6.4 VS6.1±3.1歲）的趨勢並連同有低的心臟速率、低的射血前期值和較多的體重減輕、較高的左心室射血期。這可能顯示出，這非介入組的運動員可能沒有達到心臟疲勞的階段。 在跑步的總距離成績分組中，我們發現，跑出較多距離的超級馬拉松選手與左心室射血期縮短有關，當心臟開始衰竭時這個標記就會開始下降（-45.92±26.09 VS -6.29±37.61，P=0.024）。換句話說漫長高壓的運動將導致急性可逆的臨床非顯著的心臟功能惡化。有趣的是在體重流失議題分組中，我們發現，更多的體重減少與心臟機能有關而較多體重減少的參賽者具有較低的胸腔液體指數（-0.71±4.82 VS 3.38±3.66，P =0.046）。這個指標是說明跑者胸腔液體的量，這較低的胸腔液體指數是證明運動員有較多的體重減輕具有較好的心臟功能的證據。在血壓下降組別中，並沒有檢測出能說明臨床顯著心臟功能變化的證據。
結論：我們目前的研究顯示電子心力測量法，此一設備運用在超級馬拉松跑者，測量其心臟功能與協助賽者治療或救護上是個能提供其效能的工能性機具。在電子心力測量法監測下也發現，劇烈運動會引起急性可逆的臨床非顯著心臟功能惡化。
Objective:
To investigate cardiac function measurements and athletic performance by Noninvasive Method with Electrical Cardiometery among elite participants in 24 hour ultra-marathon.
Methods:
This is a prospective study, where twenty endurance athletes completed 24 hour runs on a 400m track. Cardiac function measurements were taken a day before, immediately after the race and 24 hour post race. All enrolled athletes than were classified into four groups according to 1.) Received intravenous hydration intervention or not, 2.) Total running distances greater than 200km or not, 3.) Body weight change greater than 3 percent or not, and 4.) Blood pressure declined over 10 percent or not. Both cardiac fatigue phase and recovery phase were than discussed in detail before all subjects divided into groups and after divided into groups, in order to assess cardiac function and performance.
Results:
Before stratify participants into groups, cardiac fatigue phase of all subjects is represented by a decline in left ventricular ejection time (289.7 ± 29.4 versus 257.6 ± 31.3 msec, P <0.002), an incline of cardiac output (4.3 ± 1.0 versus 5.4 ± 1.2 L/min, P =0.007) and heart rate at laying, seating and standing (64.2 ± 10.7 versus 81.5 ± 13.6 b P < 0.001; 66.1 ± 8.5 versus 86.2 ± 14.3 bpm, P <0.001; 73.2 ± 10.9 versus 92.8 ± 13.2 bpm, P <0.001). As well as body weight loss is observed (59.2 ± 6.1 versus 57.7 ± 5.9 kilograms, P < 0.001). Recovery phase is characterized by all cardiac function measurements and body weight returned back to baseline values. Even though this is not statistically significant, when breakdown each group individually, group 1 where athletes whom did not receive IV intervention showed a trend of a more senior marathon running experience (8.3 ± 6.4 vs 6.1 ± 3.1 years) along with a lower heart rate, pre-ejection period values and higher left ventricular ejection time with higher body weight loss were also seen in the non-intervention group. This may indicate that athletes in this group may not be approaching cardiac fatigue phase. In group 2, we have found that greater distance covered is associated with a decline in left ventricular ejection time (-45.92 ± 26.09 vs -6.29 ± 37.61, P=0.024) which when heart starts to fail this marker will begin to decrease. This in turn may be interpreted as prolong exercise will cause acute reversible clinically non-significant worsening in cardiac function. Interesting in group 3, we have found that performance is associated with greater body weight loss and participants with greater body weight loss have a lower thoracic fluid index (-0.71 ± 4.82 vs 3.38 ± 3.66, P = 0.046). This is a marker illustrating amount of fluid in the patient’s chest cavity, as a result this may be evidence demonstrating athletes with greater body weight loss have better cardiac function. In group 4, no evidence of suggesting clinically significant cardiac function changes were detected.
Conclusion:
Our current study indicates that the electric Cardiometry device is a useful device in measuring cardiac function during an ultramarathon setting. As well as, strenuous exercise will cause acute reversible clinically non-significant worsening in cardiac function. |
