Wheelchair propulsion: effects of experience and push strategy on efficiency and perceived exertion

2008 ◽  
Vol 33 (5) ◽  
pp. 870-879 ◽  
Author(s):  
John P. Lenton ◽  
Neil E. Fowler ◽  
Lucas van der Woude ◽  
Victoria L. Goosey-Tolfrey
Keyword(s):  
Oxygen Consumption ◽  
Perceived Exertion ◽  
Maximal Exercise ◽  
Metabolic Cost ◽  
Peak Oxygen Consumption ◽  
Wheelchair Propulsion ◽  
Physiological Measures ◽  
Frequency Data ◽  
Ratings Of Perceived Exertion

The purpose of this study was to examine the role of wheeling experience on efficiency, metabolic cost, and differentiated ratings of perceived exertion (RPEs) during synchronous and asynchronous hand-rim propulsion with varying arm frequencies. Fourteen able-bodied (AB) male participants and 8 male wheelchair sportsmen (WS) performed tests of peak oxygen consumption for both propulsion modes. Subsequently, 2 series of five 4-min sub-maximal exercise bouts were completed at an individualized velocity (60% of peak oxygen consumption). Arm frequencies consisted of the freely chosen frequency (FCF), followed by 4 counter-balanced paced trials pushing at 60%, 80%, 120%, and 140% of the FCF. Efficiency indices (gross, GE; work, WE) were determined and peripheral (RPE-P), central (RPE-C), and overall (RPE-O) RPEs were recorded. The GE (6.4% vs. 8.4%) and WE (11.3% vs. 15.1%) were significantly higher in WS than in AB (p = 0.001). Trends in the oxygen consumption, GE, and WE data were similar in both groups, propulsion mode, and arm frequency. Data suggest that 80% FCF resulted in improved efficiency for both propulsion mode and group, although the differences between those arm frequencies immediately above and below were non-significant. Lower RPE scores corresponded with higher efficiency values. Regardless of group there were significant differences (p = 0.001) between the differentiated RPE measures, whereby RPE-P was on average always the highest score (13.1) and RPE-C the lowest (11.1; RPE-O was 12.2). In conclusion, despite the anticipated differences in efficiency between the WS and AB participants, this study confirmed that psycho-physiological measures produce similar trends to physiological measures with manipulations of both arm frequency and propulsion mode.

Performance Effects of Carbohydrate Ingestion Between Bouts of Intense Aerobic Interval Exercise

2020 ◽  
Vol 15 (2) ◽  
pp. 262-267
Author(s):  
Devin G. McCarthy ◽  
Lawrence L. Spriet
Keyword(s):  
Oxygen Consumption ◽  
Perceived Exertion ◽  
Peak Oxygen Consumption ◽  
Trial Duration ◽  
Carbohydrate Ingestion ◽  
Subsequent Performance ◽  
Performance Effects ◽  
Improved Performance ◽  
Post Hoc ◽  
Glycogen Stores

Background: Rest between training sessions can be short for athletes. In these situations, consuming carbohydrate (CHO) postexercise replenishes glycogen stores, which is important for recovery and subsequent performance. Purpose: This study tested whether CHO intake during a 2-hour rest between exercise bouts improved performance in the subsequent bout. Methods: In a randomized, single-blinded, crossover design, 10 recreationally active participants (23 [4] y, 70.8 [6.6] kg, 47.0 [5.4] mL·O2·min−1·kg·body·mass−1) arrived at the lab postprandial and completed 2 exercise bouts separated by a 2-hour rest. Bouts included 5 × 4-minute intervals at ∼80% peak oxygen consumption separated by 2 minutes at ∼40% peak oxygen consumption and ended with an endurance trial to voluntary exhaustion at ∼90% peak oxygen consumption. During intervals 1 and 4 in each bout, expired gases were collected and O2 deficit was estimated. Immediately following bout 1, either a CHO (1.2 g CHO·kg·body·mass−1) or placebo solution was consumed. Results: Endurance trial duration decreased in bout 2 versus 1 in both conditions (P < .01) but was ∼35% longer in bout 2 with CHO versus placebo (interaction, P = .03; post hoc, P = .03). Oxygen uptake increased during interval 4 versus 1 in both bouts (P < .01) but was unaffected by CHO (P ≥ .58). O2 deficit was unaffected by CHO (P = .93), bout, or interval (P ≥ .15). Perceived exertion was higher in bout 2 versus 1 (P < .001) and reduced in intervals 2 and 4 in CHO (P ≤ .01). Conclusions: When rest between training sessions is 2 hours, athletes may improve subsequent performance by consuming CHO during recovery.

scholarly journals The acute physiological and perceptual effects of recovery interval intensity during cycling-based high-intensity interval training

2020 ◽  
Author(s):  
Christopher R. J. Fennell ◽  
James G. Hopker
Keyword(s):  
Oxygen Consumption ◽  
High Intensity ◽  
Lactate Threshold ◽  
Interval Training ◽  
Peak Oxygen Consumption ◽  
High Intensity Interval Training ◽  
Active Recovery ◽  
Recovery Interval ◽  
High Intensity Interval

Abstract Purpose The current study sought to investigate the role of recovery intensity on the physiological and perceptual responses during cycling-based aerobic high-intensity interval training. Methods Fourteen well-trained cyclists ($$\dot{V}{\text{O}}_{{{\text{2peak}}}}$$ V ˙ O 2peak : 62 ± 9 mL kg−1 min−1) completed seven laboratory visits. At visit 1, the participants’ peak oxygen consumption ($$\dot{V}{\text{O}}_{{{\text{2peak}}}}$$ V ˙ O 2peak ) and lactate thresholds were determined. At visits 2–7, participants completed either a 6 × 4 min or 3 × 8 min high-intensity interval training (HIIT) protocol with one of three recovery intensity prescriptions: passive (PA) recovery, active recovery at 80% of lactate threshold (80A) or active recovery at 110% of lactate threshold (110A). Results The time spent at > 80%, > 90% and > 95% of maximal minute power during the work intervals was significantly increased with PA recovery, when compared to both 80A and 110A, during both HIIT protocols (all P ≤ 0.001). However, recovery intensity had no effect on the time spent at > 90% $$\dot{V}{\text{O}}_{{{\text{2peak}}}}$$ V ˙ O 2peak (P = 0.11) or > 95% $$\dot{V}{\text{O}}_{{{\text{2peak}}}}$$ V ˙ O 2peak (P = 0.50) during the work intervals of both HIIT protocols. Session RPE was significantly higher following the 110A recovery, when compared to the PA and 80A recovery during both HIIT protocols (P < 0.001). Conclusion Passive recovery facilitates a higher work interval PO and similar internal stress for a lower sRPE when compared to active recovery and therefore may be the efficacious recovery intensity prescription.

scholarly journals Cross-validation of Peak Oxygen Consumption Prediction Models From OMNI Perceived Exertion

2016 ◽  
Vol 37 (10) ◽  
pp. 831-837
Author(s):  
R. Mays ◽  
F. Goss ◽  
E. Nagle ◽  
M. Gallagher ◽  
L. Haile ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Perceived Exertion ◽  
Cross Validation ◽  
Prediction Models ◽  
Peak Oxygen Consumption ◽  
Consumption Prediction

scholarly journals The Role of Cardiopulmonary Exercise Test in IPF Prognosis

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Christina Triantafillidou ◽  
Effrosyni Manali ◽  
Panagiotis Lyberopoulos ◽  
Likourgos Kolilekas ◽  
Konstantinos Kagouridis ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Exercise Testing ◽  
Risk Estimation ◽  
Minute Ventilation ◽  
Cardiopulmonary Exercise Testing ◽  
Lung Mechanics ◽  
Peak Oxygen Consumption ◽  
Exercise Limitation ◽  
Cardiopulmonary Exercise

Background. In IPF, defects in lung mechanics and gas exchange manifest with exercise limitation due to dyspnea, the most prominent and disabling symptom.Aim. To evaluate the role of exercise testing through the 6MWT (6-minute walk test) and CPET (cardiopulmonary exercise testing) in the survival of patients with IPF.Methods. This is a prospective, observational study evaluating in 25 patients the relationship between exercise variables through both the 6MWT and CPET and survival.Results. By the end of the observational period 17 patients were alive (33% mortality). Observation ranged from 9 to 64 months. VE/VCO2slope (slope of relation between minute ventilation and CO2production), VO2peak/kg (peak oxygen consumption/kg), VE/VCO2ratio at anaerobic threshold, 6MWT distance, desaturation, and DLCO% were significant predictors of survival while VE/VCO2slope and VO2peak/kg had the strongest correlation with outcome. The optimal model for mortality risk estimation was VO2peak/kg + DLCO% combined. Furthermore, VE/VCO2slope and VO2peak/kg were correlated with distance and desaturation during the 6MWT.Conclusion. The integration of oxygen consumption and diffusing capacity proved to be a reliable predictor of survival because both variables reflect major underlying physiologic determinants of exercise limitation.

scholarly journals The Role of Specific Warm-up during Bench Press and Squat Exercises: A Novel Approach

2020 ◽  
Vol 17 (18) ◽  
pp. 6882
Author(s):  
Bruno Ribeiro ◽  
Ana Pereira ◽  
Pedro P. Neves ◽  
António C. Sousa ◽  
Ricardo Ferraz ◽  
...  
Keyword(s):  
Perceived Exertion ◽  
Bench Press ◽  
Peak Velocity ◽  
Dynamic Strength ◽  
Training Load ◽  
Ratings Of Perceived Exertion ◽  
Warm Up ◽  
Novel Approach ◽  
Maximal Dynamic Strength

The current study aims to verify the effects of three specific warm-ups on squat and bench press resistance training. Forty resistance-trained males (19–30 years) performed 3 × 6 repetitions with 80% of maximal dynamic strength (designated as training load) after one of the following warm-ups (48 h between): (i) 2 × 6 repetitions with 40% and 80% of the training load (WU), (ii) 6 × 80% of training load (WU80), or (iii) 6 × 40% of the training load (WU40). Mean propulsive velocity (MPV), velocity loss (VL), peak velocity (PV), time to achieve PV, power, work, heart rates, and ratings of perceived exertion were analyzed. In squat exercises, higher MPV were found in WU80 compared with WU40 (2nd set: 0.69 ± 0.09 vs. 0.67 ± 0.06 m.s−1, p = 0.02, ES = 0.80; 3rd set: 0.68 ± 0.09 vs. 0.66 ± 0.07 m.s−1, p = 0.05, ES = 0.51). In bench press exercises, time to PV was lower in WU compared with WU40 (1st set: 574.77 ± 233.46 vs. 694.50 ± 211.71 m.s−1, p < 0.01, ES = 0.69; 2nd set: 533.19 ± 272.22 vs. 662.31 ± 257.51 m.s−1, p = 0.04, ES = 0.43) and total work was higher (4749.90 ± 1312.99 vs. 4631.80 ± 1355.01 j, p = 0.01, ES = 0.54). The results showed that force outputs were mainly optimized by WU80 in squat training and by WU in bench press training. Moreover, warming-up with few repetitions and low loads is not enough to optimize squat and bench press performances.

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