Article

The Effect of Saddle Position on Maximal Power Output and Moment Generating Capacity of Lower Limb Muscles During Isokinetic Cycling

Department of Biomedical Kinesiology, Faculty of Kinesiology and Rehabilitation Sciences, K. U. Leuven, Leuven, Belgium.
Journal of applied biomechanics (Impact Factor: 0.98). 02/2011; 27(1):1-7.
Source: PubMed

ABSTRACT

Saddle position affects mechanical variables during submaximal cycling, but little is known about its effect on mechanical performance during maximal cycling. Therefore, this study relates saddle position to experimentally obtained maximal power output and theoretically calculated moment generating capacity of hip, knee and ankle muscles during isokinetic cycling. Ten subjects performed maximal cycling efforts (5 s at 100 rpm) at different saddle positions varying ± 2 cm around the in literature suggested optimal saddle position (109% of inner leg length), during which crank torque and maximal power output were determined. In a subgroup of 5 subjects, lower limb kinematics were additionally recorded during submaximal cycling at the different saddle positions. A decrease in maximal power output was found for lower saddle positions. Recorded changes in knee kinematics resulted in a decrease in moment generating capacity of biceps femoris, rectus femoris and vastus intermedius at the knee. No differences in muscle moment generating capacity were found at hip and ankle. Based on these results we conclude that lower saddle positions are less optimal to generate maximal power output, as it mainly affects knee joint kinematics, compromising mechanical performance of major muscle groups acting at the knee.

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    • "Although the cycling assumed to be an endurance sport, the ability to achieve a high maximum power during a short period of time is an important component of success in road cycling competitions (Ebert et al., 2006; Jeukendrup et al., 2000). Maximal cycling power output largely depends on external factors like bicycle set up (Gonzalez and Hull, 1989; Too, 1990; Rankin and Neptune, 2010; Vrints et al., 2011; Yoshihuku & Herzog, 1990), pedalling cadence (Zoladz et al., 2000; Van Soest & Casius, 2000; Dorel et al., 2005; Gardner et al., 2007; Busko, 2005), cyclists position on the bike (Bertucci et al., 2008). Also internal factors like lower limbs muscle strength (Alemdaroglu, 2012; Arslan, 2005; Rannama et al., 2013; Sanding et al., 2008; Smith, 1987), muscle coordination patterns (Blake et al., 2012) and fatigue (Martin & Brown, 2009; O'Bryan et al. 2014) play important role for achieving high pedalling power. "
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    ABSTRACT: purpose of this study was to examine the asymmetries in cyclist’s lower limbs strength and in the pedalling kinematics during a seated sprinting test and to identify the relationships between asymmetries and maximal cycling power. 16 competitive road cyclists (20.6±3.7 yrs., 181.5±5.0 cm, 74.8±7.0 kg) performed 10 Sec isokinetic maximum power test with cadence 120 RPM. The asymmetry of kinematic patterns of cyclist’s upper and lower body during pedalling was registered. Separately isokinetic peak torque (PT) of main lover limbs joint were measured at angular speeds 60, 180 and 240􀀀/s. The differences in kinematic patterns and isokinetic PT values between two limbs were analysed for descriptive and inferential statistics (relative share in %, correlations and regression between asymmetry values and cycling power). Conclusion: The highest asymmetries were found in cyclist’s upper body kinematics and at the same time the most symmetrical were knee extensors strength values, but both parameters were negatively and significantly correlated with the performance of sprint cycling. By combining the leg extensors muscular strength with asymmetry of knee extensors strength and trunk kinematics the explanatory power of multiple regressions increased markedly from 0.68 to 0.92. Key words: PEAK TORQUE, ISOKINETIC DYNAMOMETRY, CYCLING KINEMATIC, STRENGTH ASYMMETRY.
    Full-text · Article · Jan 2016 · Journal of Human Sport and Exercise
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    • "The peak force applied in one cycle in submaximal conditions is more than 5 times higher during running, measured as a ground reaction force (Kyröläinen et al., 1999) than in cycling, measured as a pedal force (Farrell et al., 2003). Also the peak joint moments and power patterns in ankle, knee and hip joints are different during running stance phase than in pedal cycle at steady-state submaximal (Schache et al., 2011; Bini & Diefenthaeler, 2010; Elmer et al., 2011; William et al., 2012) and at sprinting conditions (Bezodis et al., 2012; Martin & Brown, 2009; Vrints et al., 2011; Elmer et al., 2011). The main muscle groups that are involved in cycling and running are the knee extensors and ankle plantar flexors, respectively, but in contrast to cycling, which includes mainly concentric contractions, during running the eccentric muscle actions play an important role (Bijker et al 2002; William et al., 2012). "

    Full-text · Dataset · Apr 2015
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    • "The peak force applied in one cycle in submaximal conditions is more than 5 times higher during running, measured as a ground reaction force (Kyröläinen et al., 1999) than in cycling, measured as a pedal force (Farrell et al., 2003). Also the peak joint moments and power patterns in ankle, knee and hip joints are different during running stance phase than in pedal cycle at steady-state submaximal (Schache et al., 2011; Bini & Diefenthaeler, 2010; Elmer et al., 2011; William et al., 2012) and at sprinting conditions (Bezodis et al., 2012; Martin & Brown, 2009; Vrints et al., 2011; Elmer et al., 2011). The main muscle groups that are involved in cycling and running are the knee extensors and ankle plantar flexors, respectively, but in contrast to cycling, which includes mainly concentric contractions, during running the eccentric muscle actions play an important role (Bijker et al 2002; William et al., 2012). "
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    ABSTRACT: The purpose of this study was to compare the isokinetic muscle performance of lower limbs in middle distance runners and road cyclists. Subjects: 10 competitive Estonian middle distance runners (age 23.8 ± 3.8 yrs., height 181.8 ± 2.8 cm, mass 73.6 ± 7.4kg) and 16 road cyclists (21.1 ± 3.5 yrs., 181.5 ± 5.0cm, 74.8 ± 7.0kg) volunteered in this study. Methods: Isokinetic strength of ankle plantar flexors (A-pf), ankle dorsal flexors (A-df), knee (K) and hip (H) extensors (ex) and flexors (fl) were measured with Humac NORM isokinetic dynamometer in angular speeds 60, 180 and 240 °/s. Isokinetic peak torque (PT), and power (P) values of best repetition and total work (ToW) of 15 repetitions in angular speed 240°/s were expressed as a mean of dominant and non-dominant leg. The absolute and relative isokinetic values were compared between runners and cyclists. Results: The comparison of PT values shows that cyclists have significantly (p<0.05) higher results in A-pf and K-fl in all testing speeds. No significant differences between A-df, K-ex, H-fl and H-ex PT values at any speed were found. Cyclists had also significantly higher P results in A-pf, K-fl and K-ex in all testing speeds and tendency (p=0.08) in H-ex 60°/s. ToW values of A-pf, K-ex and K-fl were significantly higher in cyclists group, but runners had higher values in H-fl. Conclusion: Cyclists have higher isokinetic muscle performance values in A-pf, K-fl, and K-ex and runners have higher total work ability in H-fl. No significant differences in A-df and H-ex performance between cyclists and runners were found. Runners and cyclists have also different power-velocity curves of A-df, H-ex, K-ex and K-fl
    Full-text · Article · Jan 2013
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