A study was conducted to clarify the exercise intensity and metabolic condition during a free routine of synchronized swimming with respect to heart rate (HR), blood lactate concentration (La) and the rate of perceived exertion (RPE) . Six well trained female synchronized swimmers participated as subjects. HR during the free routine was measured continuously. La and RPE during the free routine were measured intermittently from the start to end of each stage. Maximum heart rate (swimmingHRmax : S-HRmax) was determined by measurement of maximum oxygen uptake using a swimming flume. Peak blood lactate concentration (Peak La) was measured after the maximum front crawl stroke of 100 m. The average values and S. D. of S-HRmax and Peak La were 180.0±3.8 beats · min^-1 and 9.6 ± 1.0 mmol · 1^-1, respectively. Average values, S. D. and ranges of HR and %S-HRmax during the free routine were 137.6±25.5 (60-180) beats · min^-1 and 76.5± 14.3 (34.5-96.8) %, respectively. HR during the free routine showed a decrease in the breath-holding phase. Average values and S. D. of La, %Peak La and RPE at the fourth stage were 5.4±1.2mmol·1^-1, 57.0±17.2% and 17.7±0.8, respectively. La, %Peak La and RPE at the fourth stage were significantly higher than those at the other stages, and La, %Peak La and RPE at the third stage were significantly higher than those at the second stage. These results suggested that the overall intensity of the free routine was moderate, but that part of the free routine included high-intensity activity and the percentage of anaerobic metabolism during the free routine increased in the final stages

BACKGROUND: An increase in cardiovascular diseases has been reported following major disasters. Previous work has shown that ultrasonographic findings from ultrasound cardiography examination (UCG) increased until the 44th month after the tsunami caused by the Great East Japan Earthquake. The present study conducted UCG among victims in the tsunami disaster area and investigated the frequency of disaster-related cardiovascular diseases and changes over time until the 55th month after the disaster. METHODS: The subjects were residents of temporary housing complexes and neighboring housing in Watari-gun, Miyagi Prefecture, Japan. There were 207 subjects in the 18th month, 125 in the 30th month, 121 in the 44th month, and 106 in the 55th month after the disaster. Data were collected through UCG and self-report questionnaire. RESULTS: Significant changes were observed among subjects with clinical findings from the UCG, which increased over the study period-from 42.0 to 60.8, 72.7, and 73.6% beginning in the 18th month after the disaster (p < 0.0001). CONCLUSIONS: It is possible that the UCG can become a useful examination to visualize the potential impact of a major disaster on the cardiac function of victims. Victims with clinical findings continued increasing not only during the acute phase after a disaster but also in the long term. We therefore need to keep this in mind, and note that it is important to establish a support system to control cardiovascular diseases from the early stage of disaster. TRIAL REGISTRATION UMIN; ID000029802. R000034050 . 2 November 2017.
Aged ; Aged, 80 and over ; Cardiovascular Diseases ; diagnosis ; diagnostic imaging ; Case-Control Studies ; Disasters ; statistics & numerical data ; Earthquakes ; Female ; Health Behavior ; Humans ; Japan ; Male ; Middle Aged ; Tsunamis