Validation of Plantar Pressure and Reaction Force Measured by Moticon Pressure Sensor Insoles on a Concept2 Rowing Ergometer

The purpose of this study was to determine the reliability and validity of plantar pressure and reaction force measured using the Moticon and Pedar-x sensor insoles while rowing on a Concept2 ergometer. Nineteen participants performed four 500 m trials of ergometer rowing at 22–24 strokes/min; two trials wearing Moticon insoles and two wearing Pedar-x insoles in a randomised order. Moticon and Pedar-x insoles both showed moderate to strong test–retest reliability (ICC = 0.57–0.92) for mean and peak plantar pressure and reaction force. Paired t-test demonstrated a significant difference (p < 0.001) between Moticon and Pedar-x insoles, effect size showed a large bias (ES > 1.13), and Pearson’s correlation (r < 0.37) showed poor agreement for all plantar pressure and reaction force variables. Compared to Pedar-x, the Moticon insoles demonstrated poor validity, however, the Moticon insoles had strong reliability. Due to poor validity, caution should be used when considering Moticon insoles to assess changes in pressure and force reliably over time, across multiple trials or sessions. Moticon’s wireless and user-friendly application would be beneficial for assessing and monitoring biomechanical parameters in rowing if validity between measures of interest and Moticon’s results can be established.

The Effect of Inspiratory Muscle Warm-Up on VO2 Kinetics during Submaximal Rowing

The aim of the study was to investigate the effect of an inspiratory muscle warm-up on the VO2 kinetics during submaximal intensity ergometer rowing. Ten competitive male rowers (age 23.1 ± 3.8 years; height 188.1 ± 6.3 cm; body mass 85.6 ± 6.6 kg) took part in this investigation. A submaximal constant intensity (90% PVO2max) rowing test to volitional exhaustion was carried out twice with the standard rowing warm-up (Test 1) and with the standard rowing warm-up with additional specific inspiratory muscle warm-up of two sets of 30 repetitions at 40% maximal inspiratory pressure (Test 2). We found a significant correlation between time constant (τ1) and the VO2 value at 400 s in Test 1 (r = 0.78; p < 0.05); however, no correlation was found between those parameters in Test 2. In addition, we found a positive association between VO2max from the incremental rowing test and τ1 from Test 1 (r = 0.71; p < 0.05), whereas VO2 did not correlate with τ1 from Test 2. Adding inspiratory muscle warm-up of 40% maximal inspiratory pressure to regular rowing warm-up had no significant effect on oxygen consumption kinetics during submaximal rowing tests.

Case Report: Adjusting Seat and Backrest Angle Improves Performance in an Elite Paralympic Rower

Paralympic rowers with functional impairments of the legs and trunk rely on appropriate seat configurations for performance. We compared performance, physiology, and biomechanics of an elite Paralympic rower competing in the PR1 class during ergometer rowing in a seat with three different seat and backrest inclination configurations. Unlike able-bodied rowers, PR1 rowers are required to use a seat with a backrest. For this study, we examined the following seat/backrest configurations: conA: 7.5°/25°, conB: 0°/25°, and conC: 0°/5° (usually used by the participant). All data was collected on a single day, i.e., in each configuration, one 4-min submaximal (100 W) and one maximal (all-out) stage was performed. The rowing ergometer provided the average power and (virtual) distance of each stage, while motion capture provided kinematic data, a load cell measured the force exerted on the ergometer chain, and an ergospirometer measured oxygen uptake (V˙O2). Where appropriate, a Friedman's test with post-hoc comparisons performed with Wilcoxon signed-ranked tests identified differences between the configurations. Despite similar distances covered during the submaximal intensity (conA: 793, conB: 793, conC: 787 m), the peak force was lower in conC (conA: 509, conB: 458, conC: 312 N) while the stroke rate (conA: 27 conB: 31, conC: 49 strokes·min−1) and V˙O2 (conA: 34.4, conB: 35.4, conC: 39.6 mL·kg−1·min−1) were higher. During the maximal stage, the virtual distances were 7–9% longer in conA and conB, with higher peak forces (conA: 934 m, 408 N, conB: 918 m, 418 N, conC: 856 m, 331 N), and lower stroke rates (conA: 51, conB: 54, conC: 56 strokes·min−1), though there was no difference in V˙O2peak (~47 ml−1·kg−1·min−1). At both intensities, trunk range of motion was significantly larger in configurations conA and conB. Although fatigue may have accumulated during the test day, this study showed that a more inclined seat and backrest during ergometer rowing improved the performance of a successful Paralympic PR1 rower. The considerable increase in ergometer rowing performance in one of the top Paralympic rowers in the world is astonishing and highlights the importance of designing equipment that can be adjusted to match the individual needs of Paralympic athletes.

Antiphase crew rowing on water: a first case study.

In crew rowing, agents need to mutually coordinate their movements to achieve optimal performance (De Poel, De Brouwer, &amp; Cuijpers, 2016). Traditionally, rowers aim to achieve perfect synchronous (in-phase) coordination. Somewhat counterintuitively, however, crew rowing in an antiphase pattern (i.e., alternating strokes) would actually be mechanically more efficient: it diminishes the within-cycle surge velocity fluctuations of the boat, thereby reducing hydrodynamic drag and hence power losses with 5-6% (Brearly &amp; DeMestre, 1998; De Poel et al., 2016; De Brouwer, De Poel, &amp; Hofmijster, 2013; Cuijpers, Zaal, &amp; De Poel, 2015, Greidanus, Delfos, &amp; Westerweel, 2016). However, from coordination dynamics an antiphase pattern is expected to be less stable, especially at high stroke rates such as in racing, which may even lead to transitions to the more stable in-phase pattern (Haken, Kelso, &amp; Bunz, 1985). Recent laboratory studies in which rower dyads performed antiphase crew coordination on two mechanically coupled ergometers have provided promising results (De Brouwer et al., 2013; De Poel et al., 2016; Cuijpers et al., 2015;). However, counter to ergometer rowing, rowing on-water also requires handling of the oars and boat movements in three dimensions, such as lateral balance and forward speed. Furthermore, the boat has actual forward speed. Therefore, the next step in this endeavour is to examine antiphase crew rowing and associated boat movements on water. Here we report results of the first test case.

Pengaruh Kelelahan Terhadap Kinematik Atlet Rowing

Kelelahan merupakan faktor yang dapat mempengaruhi kualitas gerak seorang atlet, salah satunya yaitu kinematik seorang atlet seperti perubahan pada postur, sudut sendi, dan kordinasi antar sendi ketika atlet tersebut mengalami kelelahan. Oleh karena itu tujuan dari penelitian ini adalah untuk mengetahui pengaruh kelelahan terhadap kinematik atlet rowing UKM Dayung UPI. 10 orang anggota Unit Kegiatan Mahasiswa Dayung UPI nomor rowing berpartisipasi dalam penelitian ini. Desain yang digunakan dalam penelitian ini adalah One Group Pretest – Posttest Design. Instrument pengambilan data menggunakan 1 handycams (Sony 32GB HDR-PJ540), 1 Accutrend Plus, 100-meter ergometer rowing test, dan Burpee (Squat Thrust). Penelitian ini dianalisis dengan menggunakan Paired Sample T-test, dengan tingkat (Sig. 0.05). Hasil dari penelitian ini menunjukan bahwa terdapat perbedaan yang signifikan pada Angle of Hip Joint at Finish Phase (p= 0.005), Angle of Knee Joint at Finish Phase (p= 0.007), Angular Velocity of Hip Joint at Drive Phase (p= 0.006), dan Angular Velocity of Knee Joint at Drive Phase (p= 0.027) saat atlet rowing mengalami kelelahan. Hal ini menunjukan bahwa kelelahan dapat menjadi salah satu faktor yang mempengaruhi kinematik atlet rowing.

Exploring the Limitations of Event-Related Potential Measures in Moving Subjects: Pilot Studies of Four Different Technical Modifications in Ergometer Rowing

Measuring brain activity in moving subjects is of great importance for investigating human behavior in ecological settings. For this purpose, EEG measures are applicable; however, technical modifications are required to reduce the typical massive movement artefacts. Four different approaches to measure EEG/ERPs during rowing were tested: (i) a purpose-built head-mounted preamplifier, (ii) a laboratory system with active electrodes, and a wireless headset combined with (iii) passive or (iv) active electrodes. A standard visual oddball task revealed very similar (within subjects) visual evoked potentials for rowing and rest (without movement). The small intraindividual differences between rowing and rest, in comparison to the typically larger interindividual differences in the ERP waveforms, revealed that ERPs can be measured reliably even in an athletic movement such as rowing. On the other hand, the expected modulation of the motor-related activity by force output was largely affected by movement artefacts. Therefore, for a successful application of ERP measures in movement research, further developments to differentiate between movement-related neuronal activity and movement-related artefacts are required. However, activities with small magnitudes related to motor learning and motor control may be difficult to detect because they are superimposed by the very large motor potential, which increases with force output.

Fully Coupled Modeling of Athlete Force Application and Power Transfer in Rowing Ergometry

A fully coupled model of an athlete’s muscular force output combined with a load resistance is developed and investigated in context of ergometer rowing. The athlete force is based on a simple Hill equation hyperbolic-in-speed, and parabolic-in-length model. Coupling this force function with the dynamics of the ergometer load and inertia and athlete’s own body mass inertia produces a trajectory of the resultant motion in force-speed-length space. The coupled equations were solved using a first order time-marching procedure, and iteratively calculated starting conditions based on ergometer spin-down during the recovery period between strokes. The results agree well with experimental measurements available from Kleshnev particularly given the relatively simple, and untuned, athlete force model used. Changing the load resistance changed the trajectory of the stroke, with qualitative agreement with the expected outcomes.

Validity of testing and training using the kayak ergometer

Background and Study Aim. The paper is dedicated to the problem of the strength testing and training using the ergometer rowing performance in the flat water kayak sport. The aim of the research was to create a model of validity based on the relationship between the ergometer and on-water performance competition rowing. Material and Methods. Nineteen 15-17 years old male kayak rowers during the off-season were randomly divided into two groups. An experimental group trained according the same program as the control group, but two times a week a part of the common strength training exercises was substituted with a high-intensity strength training using the ergometer rowing. A whole amount of strength loading on all the rowers of the two groups was equal. Validity of testing and training of the ergometer rowing in the kayak sport was evaluated using interclass correlation between competition performance on 500 m on-water kayak and ergometer rowing. Results. Strong significant correlation is revealed between competition performance of on-water kayak and ergometer rowing before and after the off-season (| r | = 0.892, 0.902, p <0.001), that shows rather good validity. Other result of the correlation analysis shows good prognostic ability of the ergometer performance regarding competition performance of on-water kayaking (| r | = 0.913). Conclusions. The proposed model based on the relationship between the ergometer and on-water performance competition rowing shows rather good validity of the strength testing and training in the on-water kayak sport.