James Balmer

Peak power predicts performance power during an outdoor 16.1-km cycling time trial

PURPOSE To assess i) the reproducibility of peak power output recorded during a maximal aerobic power test (MAP), and ii) its validity to predict endurance performance during a field based 16.1-km time trial (16.1-km TT). METHODS Two studies were completed: for part I, nine subjects performed three MAP tests; for part II, 16 subjects completed a MAP test and 16.1-km TT. Power output was recorded using an SRM power meter and was calculated as peak power output (PPO) recorded during 60 s of MAP and mean power output for the 16.1-km TT (16.1-km TT(PO)). RESULTS There was no difference between PPO recorded during the three MAP trials, mean coefficient of variation for individual cyclists was 1.32% (95%CI = 0.97-2.03), and test-retest reliability expressed as an intraclass correlation coefficient was 0.99 (95%CI = 0.96-1.00). A highly significant relationship was found between PPO and 16.1-km TT(PO) (r = 0.99, P < 0.001) but not for PPO and 16.1-km TT time (r = 0.46. P > 0.05). CONCLUSION The results show that PPO affords a valid and reliable measure of endurance performance which can be used to predict average power during a 16.1-km TT but not performance time.

Is Cardiorespiratory Fitness Related to Quality of Life in Survivors of Breast Cancer

The purpose of this study was to investigate whether indices of cardiorespiratory fitness are related to quality of life (QOL) in women survivors of breast cancer. Using the European Organization for Research and Treatment of Cancer QLQ-30 questionnaire, we assessed the QOL of 16 participants (age, 50 ± 9 years; body mass, 66.6 ± 9.6 kg). All participants performed incremental cycle ergometer exercise to determine several indices of cardio-respiratory fitness (e.g., peak oxygen uptake [&OV0312;O2peak, in L·min−1, ml·kg−1·min−1]), peak power output (PPO, in W), PPO/ body mass (W·kg−1), peak heart rate (HRpeak, b·min−1), peak ventilation (VEpeak), and &OV0312;O2 and heart rate (HR) at the ventilatory (VT) and respiratory compensation (RCT) thresholds. Relationships between QOL and variables were assessed using Spearman rank-difference correlation tests. A significant inverse relationship (p < 0.05) was found for QOL scores and values for age (years) and body mass (kg) (ρ = −0.53), %HRpeak@VT (ρ = −0.59) and %VEpeak@VT (ρ = −0.61). A significant positive relationship (p < 0.05) was found for QOL and PPO/body mass (ρ =0.59) and HRpeak (ρ = 0.78), &OV0312;O2@RCT (ml·kg−1·min−1)(ρ = 0.51), power output (PO, expressed as either W or W·kg−1) at RCT, and HR at RCT (ρ = 0.54). No other significant relationship was found between QOL and variables obtained from the tests. In conclusion, these findings highlight possible relationships between cardiorespiratory fitness and well-being in survivors of breast cancer. From a practical point of view, our data emphasize the need for this population to engage in programmed cardiorespiratory exercise training, mainly designed to improve VT and RCT. The improvement of both submaximal indices can have a beneficial effect on QOL.

Indoor 16.1-km time-trial performance in cyclists aged 25 – 63 years

Abstract In this study, we assessed age-related changes in indoor 16.1-km cycling time-trial performance in 40 competitive male cyclists aged 25 – 63 years. Participants completed two tests: (1) a maximal ramped Kingcycle™ ergometer test, with maximal ramped minute power (RMPmax, W) recorded as the highest mean external power during any 60 s and maximal heart rate (HRmax, beats · min−1) as the highest value during the test; and (2) an indoor Kingcycle 16.1-km time-trial with mean external power output (W), heart rate (beats · min−1), and pedal cadence (rev · min−1) recorded throughout the event. Results revealed age-related declines (P < 0.05) in absolute and relative time-trial external power output [(24 W (7.0%) per decade], heart rate [7 beats · min−1 (3.87%) per decade], and cadence [3 rev · min−1 (3.1%) per decade]. No relationships (P > 0.05) were observed for mean power output and heart rate recorded during the time-trial versus age when expressed relative to maximal ramped minute power and maximal heart rate respectively. Strong relationships (P < 0.05) were observed for maximal ramped minute power and time-trial power (r = 0.95) and for maximal heart rate and time-trial heart rate (r = 0.95). Our results show that indoor 16.1-km time-trial performance declines with age but relative exercise intensity (%RMPmax and %HRmax) does not change.

Reliability of an air-braked ergometer to record peak power during a maximal cycling test

PURPOSE To assess the reliability of the Kingcycle ergometer, this study compared peak power recorded using a Kingcycle and SRMTM power meters during Kingcycle maximal aerobic power tests. METHODS The study was completed in two parts: for part 1, nine subjects completed three maximal tests with a stabilizing kit attached to the Kingcycle rig and calibration of the Kingcycle checked against SRM (MAP(C)); and for part 2, nine subjects completed two maximal tests without the stabilizing kit and the Kingcycle calibrated using the standard procedure (MAP(S)). Each MAP(C) test was separated by 1 wk; however, MAPs tests were separated by 54 +/- 32 d, (mean +/- SD). Testing procedure was repeated for each MAP and peak power output was calculated as the highest average power output recorded during any 60-s period of the MAP test using the Kingcycle (King(PPO)) and SRM (SRM(PPO)). RESULTS Coefficient of variations (CVs) for King(PPO) were larger than those of SRM(PPO); 2.0% (95%CI = 1.5-3.0) versus 1.3% (95%CI = 1.0-2.0) and 4.6% (95%CI = 2.7-7.6) versus 3.6% (95%CI = 2.1-6.0) for MAPC( and MAP(S), respectively. During all tests, King(PPO) was higher than SRM(PPO) by an average of approximately 10% (P < 0.001). CONCLUSIONS Investigators should be aware of the discrepancy between the two systems when assessing peak power and that SRM cranks provide a more reproducible measure of peak power than the Kingcycle ergometer.

Mechanically braked Wingate powers: agreement between SRM, corrected and conventional methods of measurement

In this study, we assessed the agreement between the powers recorded during a 30 s upper-body Wingate test using three different methods. Fifty-six men completed a single test on a Monark 814E mechanically braked ergometer fitted with a Schoberer Rad Messtechnik (SRM) powermeter. A commercial software package (Wingate test kit version 2.21, Cranlea, UK) was used to calculate conventional and corrected (with accelerative forces) values of power based on a resistive load (5% body mass) and flywheel velocity. The SRM calculated powers based on torque (measured at the crank arm) and crank rate. Values for peak 1 and 5 s power and mean 30 s power were measured. No significant differences (P >0.05) were found between the three methods for 30 s power values. However, the corrected values for peak 1 and 5 s power were 36 and 23% higher (P <0.05) respectively than those for the conventional method, and 27 and 16% higher (P <0.05) respectively than those for the SRM method. The conventional and SRM values for peak 1 and 5 s power were similar (P >0.05). Power values recorded using each method were influenced by sample time (P <0.05). Our results suggest that these three measures of power are similar when sampled over 30 s, but discrepancies occur when the sample time is reduced to either 1 or 5 s.

Reproducibility of power production during sprint arm ergometry

Sprint tests are frequently used to evaluate between- subject differences and can provide a valuable insight into performance capacity. The present study determined the reproducibility of peak and mean power output during upper-body sprints. After familiarization 25 men (mean [± SD] age 29 [6] years, body mass 82.8 [12.7] kg and height 1.76 [0.05] m) completed 2 20-second upper-body sprint tests using an adapted cycle ergometer. Mean (± SD) values of all power (uncorrected and corrected) measurements achieved during the 2 tests were checked for systematic bias using separate paired t-tests. Test- retest reproducibility was examined using coefficients of variation and single-measure intraclass correlation coefficients, as well as an assessment of the typical (random) error and the 95% limits of agreement. The value of corrected peak power (628 [167] W) was higher (p < 0.05) compared with the uncorrected value (509 [109] W). Values of corrected (465 [95] W) and uncorrected (444 [87] W) mean power were similar (p > 0.05). The mean bias value for all power parameters equated to less than =1% of the absolute values of power measured. Intraclass correlation coefficients for all data sets ranged from 0.97 to 0.98. Coefficients of variation for uncorrected and corrected values of peak power were 2.8 and 4.5%, while corresponding values for mean power were 2.9 and 3.2%, respectively. The reproducibility of all power indices was below 5%. The results of this study indicate that both uncorrected and corrected measurements of peak power output and mean power output can be used to assess performance during sprint arm ergometry.

Effect of age on 16.1-km time-trial performance

Abstract In this study, we assessed the performance of trained senior (n = 6) and veteran (n = 6) cyclists (mean age 28 years, s = 3 and 57 years, s = 4 respectively). Each competitor completed two cycling tests, a ramped peak aerobic test and an indoor 16.1-km time-trial. The tests were performed using a Kingcycle™ ergometer with the cyclists riding their own bicycle fitted with an SRM™ powermeter. Power output, heart rate, and gas exchange variables were recorded continuously and blood lactate concentration [HLa] was assessed 3 min after the peak ramped test and at 2.5-min intervals during the time-trial. Peak values for power output (RMPmax), heart rate (HRpeak), oxygen uptake ([Vdot]O2peak), and ventilation ([Vdot] Epeak) attained during the ramped test were higher in the senior group (P < 0.05), whereas [HLa]peak, RERpeak, [Vdot] E:[Vdot]O2peak, and economypeak were similar between groups (P > 0.05). Time-trial values (mean for duration of race) for power output (WTT), heart rate (HRTT), [Vdot]O2 ([Vdot]O2TT), and [Vdot] E ([Vdot] ETT) were higher in the seniors (P < 0.05), but [HLa]TT, RERTT, [Vdot] ETT:[Vdot]O2TT, and economyTT were similar between the groups (P > 0.05). Time-trial exercise intensity, expressed as %RMPmax, %HRpeak, %[Vdot]O2peak, and %[Vdot] Epeak, was similar (P > 0.05) for seniors and veterans (WTT: 81%, s = 2 vs. 78%, s = 8; HRTT: 96%, s = 4 vs. 94%, s = 4; [Vdot]O2TT: 92%, s = 4 vs. 95%, s = 10; [Vdot] ETT: 89%, s = 8 vs. 85%, s = 8, respectively). Overall, seniors attained higher absolute values for power output, heart rate, [Vdot]O2, and [Vdot] E but not blood lactate concentration, respiratory exchange ratio (RER), [Vdot] E:[Vdot]O2, and economy. Veterans did not accommodate age-related declines in time trial performance by maintaining higher relative exercise intensity.

Heart rate responses of women aged 23–67 years during competitive orienteering

Objectives: To compare the heart rate responses of women orienteers of different standards and to assess any relation between heart rate responses and age. Methods: Eighteen competitive women orienteers completed the study. They were divided into two groups: eight national standard orienteers (ages 23–67 years); 10 club standard orienteers (ages 24–67 years). Each participant had her heart rate monitored during a race recognised by the British Orienteering Federation. Peak heart rate (HRPEAK), mean heart rate (HRMEAN), standard deviation of her heart rate during each orienteering race (HRSD), and mean change in heart rate at each control point (ΔHRCONTROL) were identified. The data were analysed using analysis of covariance with age as a covariate. Results: National standard orienteers displayed a lower within orienteering race standard deviation in heart rate (6 (2) v 12 (2) beats/min, p<0.001) and a lower ΔHRCONTROL (5 (1) v 17 (4) beats/min, p<0.001). The mean heart rate during competition was higher in the national standard group (170 (11) v 158 (11) beats/min, p = 0.025). The HRMEAN for the national and club standard groups were 99 (8)% and 88 (9)% of their age predicted maximum heart rate (220−age) respectively. All orienteers aged >55 years (n = 4) recorded HRMEAN greater than their age predicted maximum. Conclusions: The heart rate responses indicate that national and club standard women orienteers of all ages participate in the sport at a vigorous intensity. The higher ΔHRCONTROL of club standard orienteers is probably due to failing to plan ahead before arriving at the controls and this, coupled with slowing down to navigate or relocate when lost, produced a higher HRSD.