Background If interplanetary travel is to be successful over the coming decades, it is essential ... more Background If interplanetary travel is to be successful over the coming decades, it is essential that countermeasures to minimize deterioration of the musculoskeletal system are as effective as possible, given the increased duration of spaceflight associated with such missions. The aim of this review, therefore, is to determine the magnitude of deconditioning of the musculoskeletal system during prolonged spaceflight and recommend possible methods to enhance the existing countermeasures. Methods A literature search was conducted using PubMed, Ovid and Scopus databases. 5541 studies were identified prior to the removal of duplicates and the application of the following inclusion criteria: (1) group means and standard deviations for pre- and post-spaceflight for measures of strength, muscle mass or bone density were reported (or provided by the corresponding author when requested via e-mail), (2) exercise-based countermeasures were included, (3) the population of the studies were huma...
Breast Cancer survivors can experience a myriad of physical and psychological benefits as a resul... more Breast Cancer survivors can experience a myriad of physical and psychological benefits as a result of regular exercise. This study aimed to build on previous research using lower impact exercise programs by using an antigravity (Alter-G(®)) treadmill to administer cardiovascular training. The purpose of this study was to determine the effectiveness a physical activity program, including an Alter-G(®) treadmill, for improving physiological and psychosocial measures in female breast cancer survivors. A 14-week intervention using an AB-AB study design was employed. Six female breast cancer survivors were recruited to participate in the study. Participants attended three 60-minute sessions per week, consisting of a combination of muscular strength/endurance, and cardiovascular endurance exercises. Consistent with current literature and guidelines, exercise interventions were individualized and tailored to suit individuals. Data was collected and analyzed in 2013. Visual inspection of re...
The increasing interest in weight loss has seen a concurrent rise in the supplemental use of ther... more The increasing interest in weight loss has seen a concurrent rise in the supplemental use of thermogenics to aid weight loss efforts. To date, the effectiveness and safety of supplemental proprietary blend thermogenics, in conjunction with high-protein energy-restricted diets have not been thoroughly evaluated. The purpose of this study was to investigate the efficacy of a low-calorie, high-protein diet with and without the concomitant use of a thermogenic supplement on body weight and body composition in apparently healthy females. Subjects were divided into three groups, Bizzy Diet+FitMiss Burn (BURN, N = 12), Bizzy Diet+Placebo (PLA, N = 13), and Control (CON, N = 14), and underwent two testing sessions separated by approximately 3 weeks. Resting blood pressure (BP), resting heart rate (RHR), clinical safety markers, body weight (BW), and body composition were assessed during each testing session. Repeated measures analysis of variance (ANOVA) revealed a significant effect for ti...
This investigation aimed to compare hydrostatic weighing (HW) with near-infrared interactance (NI... more This investigation aimed to compare hydrostatic weighing (HW) with near-infrared interactance (NIR) and skinfold measurements (SKF) in estimating body fat percentage (FAT%) in rowing athletes. FAT% was estimated in 20 elite male rowers (mean ± SD: age = 24·8 ± 2·2 years, height = 191·0 ± 6·8 cm, weight = 86·8 ± 11·3 kg, HW FAT% = 11·50 ± 3·16%) using HW with residual volume, 3-site SKF and NIR on the biceps brachii. Predicted FAT% values for NIR and SKF were validated against the criterion method of HW. Constant error was not significant for NIR (-0·06, P = 0·955) or SKF (-0·20, P = 0·813). Neither NIR (r = 0·045) nor SKF (r = 0·229) demonstrated significant validity coefficients when compared to HW. The standard error of the estimate values for NIR and SKF were both less than 3·5%, while total error was 4·34% and 3·60%, respectively. When compared to HW, SKF and NIR provide similar mean values when compared to HW, but the lack of apparent relationships between individual values and borderline unacceptable total error may limit their application in this population.
The purpose of this study was to examine the validity and reliability of estimated parameters of ... more The purpose of this study was to examine the validity and reliability of estimated parameters of the work-time relationship during cross-country ski ergometry using the traditional multi-trial critical power (CP) test and a 3 min 'all-out' test (3MT). Fourteen recreationally active male participants (mean ± SD; age: 22.14 ± 2.85 yrs; height: 177.09 ± 6.57 cm; weight: 85.68 ± 13.56 kg) completed three testing visits. All testing was conducted using an upper-body ergometer (SkiErg, Concept2, Inc., Morrisville, VT). A graded exercise test was used to determined maximal oxygen uptake (VO2peak). Two separate 3MT sessions were used to determine oxygen uptake (VO23MT), end-test power (EP), work above end-test power (WEP) and end stroke rate (ESR). Additionally, three time trials completed in a single day at simulated distances of 300 m, 650 m and 1000 m were used to estimate CP, W' and critical stroke rate (CSR). VO2peak (3.65 ± 0.50 l · min(-1)) and VO23MT (3.59 ± 0.4 l · min(-1)) were not significantly different (p = 0.162). Intraclass correlation coefficients for EP, WEP and ESR were 0.809, 0.611 and 0.783, respectively. EP (148 ± 33 W) and CP (157 ± 49 W), were not significantly different between the testing methodologies (p = 0.290) and were highly correlated (r = 0.780). WEP (8.4 ± 3.0 kJ) and W' (8.3 ± 3.0 kJ) were similar (p = 0.947) but not related (r = 0.119), while ESR (45 ± 7 spm) and CSR (47 ± 7 spm) values were not significantly different (p = 0.238) and moderately correlated (r = 0.498). The 3MT using ski ergometry was shown to produce concurrently valid results with the traditional multi-trial CP test for CP and CSR, but not W', and elicited similar maximal oxygen uptake values when compared to a graded exercise test.
Raw bioelectrical impedance analysis (BIA) data [resistance (R); reactance (Xc)] through bioelect... more Raw bioelectrical impedance analysis (BIA) data [resistance (R); reactance (Xc)] through bioelectrical impedance vector analysis (BIVA) and phase angle (PhA) have been used to evaluate cellular function and hydration status. The purpose of this investigation was to examine the effects of resistance training (RT) on classic and specific BIVA in elderly women. Twenty women (mean±SD; age: 71.9±6.9years; BMI: 24.5±3.0kgm(-2)) completed a 6-month RT program. Whole-body, single-frequency BIA, body geometry, and leg strength (5RM) measures were completed at baseline (t0), 3months (t3), and 6months (t6). The mean impedance vector displacements were compared using Hotelling's T(2) test to evaluate changes in R and Xc relative to height (R/ht; Xc/ht) or body volume (Rsp; Xcsp) estimated from the arms, legs, and trunk. 5RM, PhA, and BIVA variables were compared using ANOVA. PhA improved at t6 (p<0.01), while 5RM improved at t3 and t6 (p<0.01). Using classic BIVA, 6months (T(2)=31.6; ...
Background: Power training (PT) may be an effective modality to overcome muscle weakness for indi... more Background: Power training (PT) may be an effective modality to overcome muscle weakness for individuals with cerebral palsy (CP). The purpose of this project was to pilot test a PT intervention for individuals with CP. Methods: Using rolling recruitment, six participants were randomly assigned to either the control group (CG, n=3) or training group (TG, n=3). Investigators used the SkiergTM to simulate a unilateral, overhand throwing exercise, performed by the most affected arm. Following PT guidelines, training took place three times per week for 6 weeks. An isokinetic dynamometer was used to measure both passive and active strength pre- and post-training. Results: Although no statistically significant differences were found, a remarkable trend was observed. Shoulder extension torque increased 15% (13.97 to 16.09 Newton-meters [Nm]) for TG, compared to a 1% (9.77 to 9.90 Nm) increase for CG between pre- and post-tests. Similar results were observed in elbow extension (3.90 to 9.60...
This study evaluated the effects of creatine (Cr) loading and sex differences on aerobic running ... more This study evaluated the effects of creatine (Cr) loading and sex differences on aerobic running performance. 27 men (mean±SD; age: 22.2±3.1 years, ht: 179.5±8.7 cm, wt: 78.0±9.8 kg) and 28 women (age: 21.2±2.1 years, ht: 166.0±5.8 cm, wt: 63.4±8.9 kg) were randomly assigned to either creatine (Cr, di-creatine citrate; n=27) or a placebo (PL; n=28) group, ingesting 1 packet 4 times daily (total of 20 g/day) for 5 days. Aerobic power (maximal oxygen consumption: VO2max) was assessed before and after supplementation using open circuit spirometry (Parvo-Medics) during graded exercise tests on a treadmill. 4 high-speed runs to exhaustion were conducted at 110, 105, 100, and 90% of peak velocity to determine critical velocity (CV). Distances achieved were plotted over times-to-exhaustion and linear regression was used to determine the slopes (critical velocity, CV) assessing aerobic performance. The results indicated that Cr loading did not positively or negatively influence VO2max, CV, time to exhaustion or body mass (p&gt;0.05). These results suggest Cr supplementation may be used in aerobic running activities without detriments to performance.
ABSTRACT ROWING ERGOMETER TRAINING PROVIDES A BASIS FOR COMBAT ATHLETES TO IMPROVE AEROBIC AND AN... more ABSTRACT ROWING ERGOMETER TRAINING PROVIDES A BASIS FOR COMBAT ATHLETES TO IMPROVE AEROBIC AND ANAEROBIC FITNESS WHILE MAINTAINING LEAN BODY MASS AND DECREASING FAT MASS. THE SPECIFIC NEEDS OF COMBAT ATHLETES MAY BE MET BY TRAINING ON THE ERGOMETER BECAUSE IT INVOLVES THE COORDINATION OF BOTH THE UPPER AND THE LOWER BODY TO DEVELOP MAXIMAL STRENGTH, SPEED, AND POWER.
ABSTRACT PHOSPHATE LOADING HAS BEEN SHOWN TO INCREASE 2,3-DIPHOSPHOGLYCERATE (2,3-DPG). ELEVATED ... more ABSTRACT PHOSPHATE LOADING HAS BEEN SHOWN TO INCREASE 2,3-DIPHOSPHOGLYCERATE (2,3-DPG). ELEVATED 2,3-DPG LEVELS LEAD TO A LOWERED AFFINITY FOR OXYGEN BY HEMOGLOBIN. WITH MORE OXYGEN AVAILABLE TO THE MUSCLE, INCREASES IN EXERCISE PERFORMANCE WOULD BE EXPECTED. THE PURPOSE OF THIS REVIEW IS TO DISCUSS PREVIOUS RESEARCH AND OFFER PRACTICAL APPLICATIONS.
Background If interplanetary travel is to be successful over the coming decades, it is essential ... more Background If interplanetary travel is to be successful over the coming decades, it is essential that countermeasures to minimize deterioration of the musculoskeletal system are as effective as possible, given the increased duration of spaceflight associated with such missions. The aim of this review, therefore, is to determine the magnitude of deconditioning of the musculoskeletal system during prolonged spaceflight and recommend possible methods to enhance the existing countermeasures. Methods A literature search was conducted using PubMed, Ovid and Scopus databases. 5541 studies were identified prior to the removal of duplicates and the application of the following inclusion criteria: (1) group means and standard deviations for pre- and post-spaceflight for measures of strength, muscle mass or bone density were reported (or provided by the corresponding author when requested via e-mail), (2) exercise-based countermeasures were included, (3) the population of the studies were huma...
Breast Cancer survivors can experience a myriad of physical and psychological benefits as a resul... more Breast Cancer survivors can experience a myriad of physical and psychological benefits as a result of regular exercise. This study aimed to build on previous research using lower impact exercise programs by using an antigravity (Alter-G(®)) treadmill to administer cardiovascular training. The purpose of this study was to determine the effectiveness a physical activity program, including an Alter-G(®) treadmill, for improving physiological and psychosocial measures in female breast cancer survivors. A 14-week intervention using an AB-AB study design was employed. Six female breast cancer survivors were recruited to participate in the study. Participants attended three 60-minute sessions per week, consisting of a combination of muscular strength/endurance, and cardiovascular endurance exercises. Consistent with current literature and guidelines, exercise interventions were individualized and tailored to suit individuals. Data was collected and analyzed in 2013. Visual inspection of re...
The increasing interest in weight loss has seen a concurrent rise in the supplemental use of ther... more The increasing interest in weight loss has seen a concurrent rise in the supplemental use of thermogenics to aid weight loss efforts. To date, the effectiveness and safety of supplemental proprietary blend thermogenics, in conjunction with high-protein energy-restricted diets have not been thoroughly evaluated. The purpose of this study was to investigate the efficacy of a low-calorie, high-protein diet with and without the concomitant use of a thermogenic supplement on body weight and body composition in apparently healthy females. Subjects were divided into three groups, Bizzy Diet+FitMiss Burn (BURN, N = 12), Bizzy Diet+Placebo (PLA, N = 13), and Control (CON, N = 14), and underwent two testing sessions separated by approximately 3 weeks. Resting blood pressure (BP), resting heart rate (RHR), clinical safety markers, body weight (BW), and body composition were assessed during each testing session. Repeated measures analysis of variance (ANOVA) revealed a significant effect for ti...
This investigation aimed to compare hydrostatic weighing (HW) with near-infrared interactance (NI... more This investigation aimed to compare hydrostatic weighing (HW) with near-infrared interactance (NIR) and skinfold measurements (SKF) in estimating body fat percentage (FAT%) in rowing athletes. FAT% was estimated in 20 elite male rowers (mean ± SD: age = 24·8 ± 2·2 years, height = 191·0 ± 6·8 cm, weight = 86·8 ± 11·3 kg, HW FAT% = 11·50 ± 3·16%) using HW with residual volume, 3-site SKF and NIR on the biceps brachii. Predicted FAT% values for NIR and SKF were validated against the criterion method of HW. Constant error was not significant for NIR (-0·06, P = 0·955) or SKF (-0·20, P = 0·813). Neither NIR (r = 0·045) nor SKF (r = 0·229) demonstrated significant validity coefficients when compared to HW. The standard error of the estimate values for NIR and SKF were both less than 3·5%, while total error was 4·34% and 3·60%, respectively. When compared to HW, SKF and NIR provide similar mean values when compared to HW, but the lack of apparent relationships between individual values and borderline unacceptable total error may limit their application in this population.
The purpose of this study was to examine the validity and reliability of estimated parameters of ... more The purpose of this study was to examine the validity and reliability of estimated parameters of the work-time relationship during cross-country ski ergometry using the traditional multi-trial critical power (CP) test and a 3 min &#39;all-out&#39; test (3MT). Fourteen recreationally active male participants (mean ± SD; age: 22.14 ± 2.85 yrs; height: 177.09 ± 6.57 cm; weight: 85.68 ± 13.56 kg) completed three testing visits. All testing was conducted using an upper-body ergometer (SkiErg, Concept2, Inc., Morrisville, VT). A graded exercise test was used to determined maximal oxygen uptake (VO2peak). Two separate 3MT sessions were used to determine oxygen uptake (VO23MT), end-test power (EP), work above end-test power (WEP) and end stroke rate (ESR). Additionally, three time trials completed in a single day at simulated distances of 300 m, 650 m and 1000 m were used to estimate CP, W&#39; and critical stroke rate (CSR). VO2peak (3.65 ± 0.50 l · min(-1)) and VO23MT (3.59 ± 0.4 l · min(-1)) were not significantly different (p = 0.162). Intraclass correlation coefficients for EP, WEP and ESR were 0.809, 0.611 and 0.783, respectively. EP (148 ± 33 W) and CP (157 ± 49 W), were not significantly different between the testing methodologies (p = 0.290) and were highly correlated (r = 0.780). WEP (8.4 ± 3.0 kJ) and W&#39; (8.3 ± 3.0 kJ) were similar (p = 0.947) but not related (r = 0.119), while ESR (45 ± 7 spm) and CSR (47 ± 7 spm) values were not significantly different (p = 0.238) and moderately correlated (r = 0.498). The 3MT using ski ergometry was shown to produce concurrently valid results with the traditional multi-trial CP test for CP and CSR, but not W&#39;, and elicited similar maximal oxygen uptake values when compared to a graded exercise test.
Raw bioelectrical impedance analysis (BIA) data [resistance (R); reactance (Xc)] through bioelect... more Raw bioelectrical impedance analysis (BIA) data [resistance (R); reactance (Xc)] through bioelectrical impedance vector analysis (BIVA) and phase angle (PhA) have been used to evaluate cellular function and hydration status. The purpose of this investigation was to examine the effects of resistance training (RT) on classic and specific BIVA in elderly women. Twenty women (mean±SD; age: 71.9±6.9years; BMI: 24.5±3.0kgm(-2)) completed a 6-month RT program. Whole-body, single-frequency BIA, body geometry, and leg strength (5RM) measures were completed at baseline (t0), 3months (t3), and 6months (t6). The mean impedance vector displacements were compared using Hotelling's T(2) test to evaluate changes in R and Xc relative to height (R/ht; Xc/ht) or body volume (Rsp; Xcsp) estimated from the arms, legs, and trunk. 5RM, PhA, and BIVA variables were compared using ANOVA. PhA improved at t6 (p<0.01), while 5RM improved at t3 and t6 (p<0.01). Using classic BIVA, 6months (T(2)=31.6; ...
Background: Power training (PT) may be an effective modality to overcome muscle weakness for indi... more Background: Power training (PT) may be an effective modality to overcome muscle weakness for individuals with cerebral palsy (CP). The purpose of this project was to pilot test a PT intervention for individuals with CP. Methods: Using rolling recruitment, six participants were randomly assigned to either the control group (CG, n=3) or training group (TG, n=3). Investigators used the SkiergTM to simulate a unilateral, overhand throwing exercise, performed by the most affected arm. Following PT guidelines, training took place three times per week for 6 weeks. An isokinetic dynamometer was used to measure both passive and active strength pre- and post-training. Results: Although no statistically significant differences were found, a remarkable trend was observed. Shoulder extension torque increased 15% (13.97 to 16.09 Newton-meters [Nm]) for TG, compared to a 1% (9.77 to 9.90 Nm) increase for CG between pre- and post-tests. Similar results were observed in elbow extension (3.90 to 9.60...
This study evaluated the effects of creatine (Cr) loading and sex differences on aerobic running ... more This study evaluated the effects of creatine (Cr) loading and sex differences on aerobic running performance. 27 men (mean±SD; age: 22.2±3.1 years, ht: 179.5±8.7 cm, wt: 78.0±9.8 kg) and 28 women (age: 21.2±2.1 years, ht: 166.0±5.8 cm, wt: 63.4±8.9 kg) were randomly assigned to either creatine (Cr, di-creatine citrate; n=27) or a placebo (PL; n=28) group, ingesting 1 packet 4 times daily (total of 20 g/day) for 5 days. Aerobic power (maximal oxygen consumption: VO2max) was assessed before and after supplementation using open circuit spirometry (Parvo-Medics) during graded exercise tests on a treadmill. 4 high-speed runs to exhaustion were conducted at 110, 105, 100, and 90% of peak velocity to determine critical velocity (CV). Distances achieved were plotted over times-to-exhaustion and linear regression was used to determine the slopes (critical velocity, CV) assessing aerobic performance. The results indicated that Cr loading did not positively or negatively influence VO2max, CV, time to exhaustion or body mass (p&gt;0.05). These results suggest Cr supplementation may be used in aerobic running activities without detriments to performance.
ABSTRACT ROWING ERGOMETER TRAINING PROVIDES A BASIS FOR COMBAT ATHLETES TO IMPROVE AEROBIC AND AN... more ABSTRACT ROWING ERGOMETER TRAINING PROVIDES A BASIS FOR COMBAT ATHLETES TO IMPROVE AEROBIC AND ANAEROBIC FITNESS WHILE MAINTAINING LEAN BODY MASS AND DECREASING FAT MASS. THE SPECIFIC NEEDS OF COMBAT ATHLETES MAY BE MET BY TRAINING ON THE ERGOMETER BECAUSE IT INVOLVES THE COORDINATION OF BOTH THE UPPER AND THE LOWER BODY TO DEVELOP MAXIMAL STRENGTH, SPEED, AND POWER.
ABSTRACT PHOSPHATE LOADING HAS BEEN SHOWN TO INCREASE 2,3-DIPHOSPHOGLYCERATE (2,3-DPG). ELEVATED ... more ABSTRACT PHOSPHATE LOADING HAS BEEN SHOWN TO INCREASE 2,3-DIPHOSPHOGLYCERATE (2,3-DPG). ELEVATED 2,3-DPG LEVELS LEAD TO A LOWERED AFFINITY FOR OXYGEN BY HEMOGLOBIN. WITH MORE OXYGEN AVAILABLE TO THE MUSCLE, INCREASES IN EXERCISE PERFORMANCE WOULD BE EXPECTED. THE PURPOSE OF THIS REVIEW IS TO DISCUSS PREVIOUS RESEARCH AND OFFER PRACTICAL APPLICATIONS.
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