Whole Body Fuel Use: A Preliminary Study of Carbohydrate and Fat Oxidation During Water Exercise

The purpose of this investigation was to measure energy expenditure and whole body carbohydrate and fat oxidation during shallow water exercise (SWE; submerged to axillary level). The level of energy expenditure and the relative contribution of fuels (e.g., carbohydrate [CHO], fat) depends on the intensity of exercise effort. This descriptive study addressed two questions: (1) what is the energy expenditure of performing SWE over a range of intensities; and (2) how does the rate of CHO and fat usage change with increasingly more demanding SWE efforts. Five healthy females (ages 18 to 26 years) performed five submaximal and one maximal SWE bout based on perceived effort (Borg Scale). Indirect calorimetry (Parvo-Medic metabolic analyzer) was employed to assess metabolic response while heart rate (HR) was monitored via telemetry (Polar technology). For perception of efforts ranging from very light (~50 percent HR peak) to very hard (~88 percent HR peak), the rate of energy expenditure ranged from 3.5+0.7 to 10.5+1.3 kilocalories per minute (Kcal.min-1), while the maximal SWE effort elicited a metabolic response of 13.2+1.7 Kcal.min-1 (~ 10 X resting metabolic rate). From very light to very hard, the rate of CHO oxidation increased from 2.0+1.0 to 9.4+1.8 Kcal.min-1 (~370 percent increase), while fat oxidation remained variable among the SWE efforts. In conclusion, carbohydrate oxidation plays an increasingly more important role as a fuel source during SWE efforts that require a high rate of energy expenditure. Furthermore, this study provides insight into the energy requirements of SWE, a mode of exercise that is becoming more popular

Cardiorespiratory Responses to High Intensity Interval Shallow Water Exercise

The purpose of this study was to investigate the cardiorespiratory responses to shallow water, high intensity interval exercise (SW-HIIE). Interestingly, no studies have investigated the physiological responses of performing HIIE in a water medium. Thus, the main question of this investigation was the following: What is the physiological load imposed on the human body during an acute SW-HIIE session? Physically active females, n=9 and 26+6 yrs, volunteered for this descriptive study. Volunteers performed a familiarization trial, an incremental maximal shallow water exercise test, and a SW-HIIE session. Participants were submerged to ~75 percent of stature (axillary level). SW-HIIE consisted of 4 X 4 minute segments with one minute recovery in between each segment. Each segment consisted of 8 X 20 seconds of maximal physical effort with 10 seconds of rest between each effort. Indirect calorimetry (Parvo-Medic metabolic analyzer) was employed to assess metabolic response and heart rate was monitored via telemetry (Polar technology). SW-HIIE elicited an overall oxygen uptake response of 2.0+0.2 lO2.min-1 (73+5% of peak aerobic capacity), nearly eight times above resting metabolic rate, while overall heart rate (HR) response was 156+8 bpm (86+2% HR peak). In conclusion, the SW-HIIE session elicited cardiorespiratory responses that would be classified as vigorous on the intensity scale according to the American College of Sports Medicine’s guidelines for exercise prescription, suggesting that an acute bout of SW-HIIE imposes a great physiological load on the human body

Eating disorder risk, exercise dependence, and body weight dissatisfaction among female nutrition and exercise science university majors

Background and Aims: Past research has examined eating disorder risk among college students majoring in Nutrition and has suggested an increased risk, while other studies contradict these results. Exercise Science majors, however, have yet to be fully examined regarding their risk for eating disorders and exercise dependence. Based on pressures to fit the image associated with careers related to these two disciplines, research is warranted to examine the potential risk for both eating disorder and exercise dependence. The purpose of this study is to compare eating disorder risk, exercise dependence, and body weight dissatisfaction (BWD) between Nutrition and Exercise Science majors, compared to students outside of these career pathways. Methods: Participants (n = 89) were divided into three groups based on major; Nutrition majors (NUTR; n = 31), Exercise Science majors (EXSC; n = 30), and other majors (CON; n = 28). Participants were given the EAT-26 questionnaire and the Exercise Dependence Scale. BWD was calculated as the discrepancy between actual BMI and ideal BMI. Results: The majority of participants expressed a desire to weigh less (83%) and EXSC had significantly (p = .03) greater BWD than NUTR. However, there were no significant differences in eating disorder risk or exercise dependence among majors. Discussion and Conclusions: This study suggested there was no significant difference in eating disorder risk or exercise dependence between the three groups (NUTR, EXSC, and CON)

Cardiorespiratory Responses to a 20-minute Shallow Water Tabata Style Workout: A Gender Comparison

Purpose: To compare physiological responses to a 20-min high intensity, Tabata-style shallow water exercise workout (TS-SWE) between healthy males (M, n=9, 24±1 y) and females (F, n=9, 26±6 y)

Physiological and Psychophysical Aspects of Shallow Water Exercise

This study investigated the cardiorespiratory responses to perceptually self-regulated shallow water exercise (SR-SWE) efforts. Females (26 ± 6 years) performed a series of SWE bouts prescribed at rating of perceived exertion (RPE) 9, 11, 13, 15, and 17 (Borg scale) and an incremental, SR-SWE bout to a max of RPE 20. Oxygen uptake (VO2), heart rate (HR), and blood lactate (BLa) were monitored. VO2, HR, and BLa ranged from 0.68 ± 0.13 l·min–1, 90 ± 16 bpm, 2.0 ± 0.7 mM (RPE 9) to 2.21 ± 0.21 l·min–1, 162 ± 11 bpm, and 3.9 ± 1.6 mM (RPE 17), respectively. Peak VO2, HR, respiratory exchange ratio (RER), and BLa were 2.72 ± 0.33 l·min–1, 181 ± 7 bpm, 1.05 ± 0.05, and 8.1 ± 1.7 mM, respectively. The group linear regression equation was as follows: VO2 = –0.97 ± 0.189 (RPE), R2 = .89 (p \u3c .0001). The regression model predicted VO2 peak of 2.81 ± 0.28 l·min–1 equivalent to the measured value of 2.72 ± 0.33 l·min–1 (p = .33). Findings suggest that self-regulation of intensity based on prescribed RPE is a viable way of regulating intensity while exercising in a shallow water medium

Cardiorespiratory Responses to Shallow Water Exercise: A Sex Comparison

This investigation examinedphysiological responses to shallow waterexercise (SWE) and to a high-intensity interval SWE workout (HIISWE) in males (M, n=9) and females(F, n=9). Participants performed 5 X 5 min. SWE bouts (bts.) at ratings of perceived exertion (RPE) 9, 11, 13, 15 and 17 (Borg scale) and a maximalbout ofSWE with metabolic, heart rate (HR), and blood lactate (BLa) responses monitored. The same measurements were performed during HIISWE (4 X 4-min bts., alternating 20-s “all-out” and 10-s rest). Peak oxygen uptake (V̇O2) and BLa were greater in M (3.6±0.4 vs. 2.7±0.3 l.min-1, 10.9±1.3 vs. 8.1±1.7 mM) (p\u3c0.05), with no difference in peak HR (185±7 (M) vs. 181±7 (F) bpm). Irrespective of sex, V̇O2and HR were not different among mins. 3, 4, and 5 of ea. SWE effort (p\u3e0.05). Peak BLa for HIISWE was 11.1±2.2 (M) and 9.2±1.7 (F) mM (p\u3c0.05) with RPE ~18-19 for both sexes. Relative cardiorespiratory responses were similar between males and females during HIISWE. Perceptual self-regulation of intensity is a viable approach to controlling physiological load during SWE. Regardless of sex, HIISWE elicitedphysiological and perceptual responses categorized as “vigorous” to “near maximal to maximal” intensity bythe American College of Sports Medicine

Metabolic and Cardiovascular Responses in Older Women During Shallow-Water Exercise

The purpose of this investigation was to examine the metabolic and cardiovascular demands of shallow-water exercise in older women. Sixteen active older women who were not taking cardiac medication participated in this investigation (mean ± SE; age, 66.4 ± 1.2 years). Testing included (a) resting metabolic rate and heart rate; (b) performing 5 8-minute, evenly paced, self-selected, submaximal, shallow-water exercise bouts. Expired air was collected during the final 3 minutes of each bout while the heart rate was recorded with a Polar heart rate monitor; and (c) a 40-minute water exercise class in which heart rate was monitored. One metabolic equivalent (MET) equaled 2.7 ± 0.1 mlO2·min−1·kg−1, whereas resting heart rate was 63.4 ± 2.2 b·min−1. Average sub-maximal MET and heart rate responses for exercise bouts 1–5 ranged from 2.8 ± 0.1 to 5.8 ± 0.3 and 89.7 ± 3.0 to 119.5 ± 3.3 b·min−1, respectively. The rate of perceived exertion (RPE; Borg scale) response for bouts 1–5 ranged from 8.0 ± 0.3 to 12.5 ± 0.4. A linear relationship between MET vs. heart rate was found for each participant, with all r values greater than 0.97 (p \u3c 0.05). The estimated MET and measured HR responses for the 40-minute water exercise class were as follows: warm-up, 4.0 ± 0.3 and 99.5 ± 3.4; body of workout, 5.2 ± 0.4 and 110.0 ± 3.8 (part 1), and 5.4 ± 0.4 and 112.3 ± 3.6 (part 2); cooldown, 3.6 ± 0.3 and 95.5 ± 3.0. The exercise intensity ranged from ∼40–61% of the predicted maximum MET, and ∼66–78% of the predicted heart rate maximum. Shallow-water exercise elicits metabolic and cardiovascular responses in older women that meet the American College of Sports Medicine exercise prescription guidelines for realizing health benefits