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Optimization of hand spacing in submaximal hand cycling: a case study

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HAL Id: hal-03103407

https://hal.archives-ouvertes.fr/hal-03103407

Submitted on 8 Jan 2021

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Optimization of hand spacing in submaximal hand cycling: a case study

Geoffrey Millour, Sebastien Duc, Frédéric Puel, Hugo Moreau, William Bertucci

To cite this version:

Geoffrey Millour, Sebastien Duc, Frédéric Puel, Hugo Moreau, William Bertucci. Optimization of hand spacing in submaximal hand cycling: a case study. 2020 Science & Cycling Conference, Jun 2020, Nice, France. �hal-03103407�

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© 2020 Millour, licensee JSC. This is an Open Access article distributed under the terms of the Creative Commons Attribution License ((http://creativecommons.org/licenses/by/4.0/) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Optimization of hand spacing in submaximal hand cycling: a case study

Geoffrey Millour1, Sebastien Duc1, Frederic Puel1, Hugo Moreau2, William Bertucci1

1 Laboratoire Performance, Santé, Métrologie, Société (EA 7507), UFR STAPS, Université de Reims Champagne-Ardenne, Reims, France.

2 UFR STAPS, Université de Rennes 2, Rennes, France.

1. Background

As the medio-lateral distance between the feet in cycling, the distance between the hands in hand cycling has received little attention in scientific literature. However, Krämer et al. (2009) recommend a crank width (i.e. distance from the centres of both handles) equivalent to 85% of the inter-acromion distance (IAD) for sprint performance. Our objective was to determine optimal crank width in submaximal condition in a high-level paraplegic cyclist (44 years old, 1.75 m, 74 kg), victim of a paralysis following a compression of the D4˗D5 vertebrae.

2. Methods

During a first visit in the laboratory, the participant performed an incremental test to measure the maximal aerobic power (MAP) with his usual crank width (90% of the IAD). This cyclist previously used a crank width equal to 72% of the IAD but he had recently chosen to modify this parameter due to muscle pain. One week after the incremental test, he performed 3 tests of 8 min at 50% of MAP and at the same freely chosen pedalling cadence with three different crank widths: (1) 80% [narrow], (2) 85%

[medium] and (3) 90% [wide] of the IAD. These experimental tests were separated by 18 min: 4 min of recovery at 30% of MAP, 10 min of break to change crank width and 4 min of restart at 30% of MAP (free pedalling cadence). The tests were performed on the participant's personal handbike positioned on a standard ergometer

(Elite, Fontaniva, Italy). Crank power output (PO) was measured with a valid power meter (SRM, Jülich, Welldorf, Germany). During each test, Gross efficiency (GE; Cortex Biophysik GmbH, Leipzig, Germany), muscle activity of Trapezius Superior, Triceps Brachii, Biceps Brachii, Deltoideus Anterior, Deltoideus Posterior and Pectoralis Major of both upper limbs, which are particularly recruited in hand cycling (Arnet et al. 2012), (Delsys Trigno™

Wireless EMG, Delsys Inc., Boston, USA) and rating of perceived comfort (Millour et al. 2019) and RPE (Borg, 1982) were measured. Muscle activity was averaged for the 2 sides of the body, quantified by the root-mean-square (RMS) of the EMG signal and expressed as a percentage of the average RMS values measured during the test performed with the narrow crank width.

3. Results

Results showed constant PO and cadence for all tests (78.3 ± 0.2 W and 73.3 ± 0.7 rpm). However, GE was better with the medium crank width compared to the narrow and the wide crank widths (18.5% vs. 17.8% and 17.4%, respectively). Despite these physiological changes, RPE was equal to 10/20 for all tests and was therefore not altered by the change in crank width. On the other hand, the wider crank width led to comfort improvement (7/10, 8/10, 9/10 with the narrow, medium and wide crank widths, respectively). In addition, muscle activity (table 1) decreased for all muscles (except the Pectoralis Major) when the crank width increased.

* Correspondence: Geoffrey Millour. geoffrey.millour@univ-reims.fr

Received: 30 May 2020; Accepted: 30 June 2020; Published: 30 December 2020

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Millour et al.

Citation: Journal of Science and Cycling 2020, 9:02, 40-42

4. Conclusions

Results showed an improvement in biomechanical and subjective variables when the participant pedaled with a crank width equivalent to 90% of the IAD. Nevertheless, GE was better with the medium crank width.

Krämer et al. (2009) reported that a crank width equal to 85% of the IAD would be optimal for supra-maximal performance. Our results suggest that this crank width would also be suitable for sub-maximal performance.

However, the increased recruitment of the majority of the upper limb muscles with the narrower crank widths could explain the muscular fatigue previously reported by the participant when he used a crank width equal to 72% of the IAD. We can therefore advise this cyclist to use the medium crank width (85% of the IAD) to improve performance or a slightly larger crank width if he feels discomfort or muscle pain.

5. Acknowledgements Morphologics Company.

Keywords: Paraplegia; Gross efficiency; Muscle activity; Perceived comfort; Perceived exertion.

References

1. Arnet U, van Drongelen S, Scheel-Sailer A, van der Woude LH, Veeger DH (2012) Shoulder load during synchronous handcycling and handrim wheelchair propulsion in persons with paraplegia. Journal of Rehabilitation Medicine 44 (3):222-228.

doi:https://doi.org/10.2340/16501977-0929

2. Borg GA (1982) Psychophysical bases of perceived exertion. Medicine & Science in Sports & Exercise 14 (5):377-381.

3. Krämer C, Hilker L, Böhm H (2009) Influence of crank length and crank width on maximal hand cycling power and cadence. European Journal of Applied Physiology 106 (5):749-757.

doi:https://doi.org/10.1007/s00421-009-1062-1 4. Millour G, Duc S, Puel F, Bertucci W (2019) Comparison of two static methods of saddle height adjustment for cyclists of different morphologies.

Sports Biomechanics.

doi:10.1080/14763141.2018.1556324

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Optimization of hand spacing in submaximal hand cycling: a case study

Citation: Journal of Science and Cycling 2020, 9:02, 40-42

Table 1. Activity of 6 muscles recruited in hand cycling (average of the right and left body side) expressed as a percentage of the average RMS values measured during the test with the narrow crank width.

Trapezius (%)

Triceps (%)

Biceps (%)

Deltoideus Anterior (%)

Deltoideus Posterior (%)

Pectoralis Major (%)

Narrow 100 100 100 100 100 100

Medium 93 94 94 93 94 99

Wide 83 89 90 91 89 101

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