Influence of cycling cadence on neuromuscular activity of the knee extensors in humans

The aim of the present study was to investigate the influence of pedalling rate and power output in cycling on the neuromuscular activity of the knee extensor muscles. Ten subjects took part in 15 randomised trials, which consisted of three levels of power outputs (60%, 80% and 100% maximal aerobic power) and five cadences (70%, 85%, 100%, 115% and 130% of the freely chosen cadence, FCC). Root mean square (rms) was utilized to quantify electromyographic activity of the vastus lateralis (VL), vastus medialis (VM) and rectus femoris (RF) muscles. The mean (SD) FCC did not change with power output, ranging from 85.0 (11.9) to 88.0 (11.1) rpm. A significant power effect (P<0.01) for the rms of VL, VM and RF muscles was observed. Results showed no significant cadence effect on neuromuscular activity of the VL and VM muscles, while the rms of the RF muscle was significantly greater (P<0.05) at 70% FCC when compared to other cadences. In conclusion, the neuromuscular activity of the knee extensor muscles was not significantly influenced by cadence manipulations. Thus, minimisation of the neuromuscular activity of these muscles would not seem to lead to the choice of a cadence in cycling. Electronic Publication     

Freely chosen pedal rate during free cycling on a roller and ergometer cycling

The purpose of this study was to examine the effect of regulation of work rate, computer controlled versus controlled by the subject, on the relationship between work rate, freely chosen pedal rate (FCC) and gross efficiency. Eighteen male cyclists participated in the study. One group, freely cycling (FC) on a competition bike mounted on an electromagnetic roller, could use gearing and cadence to achieve each work rate. The other group (EC) was cycling on an ergometer which enables a constant work rate, independent of cadence. Subjects performed an increasing work rate protocol from 100 W up to exhaustion. We found a strong interaction between group and work rate on cadence (P < 0.001). In the FC group, work rate affected cadence (P < 0.001), increasing from 72 rpm at 100 W to 106 rpm at 350 W. For the EC group, no work rate effect was present (average FCC 92 rpm). Gross efficiency increased with work rate for both groups. The efficiency–cadence relationship was strongly affected by the protocol. At a given work rate, very similar efficiency values were obtained at highly different cadences. The discrepancy in the FCC-work rate relationship between the EC group and the FC group may be related to the manner in which one can regulate work rate. FCC depends not only on work rate but is also affected considerably by the manner in which the work rate can be controlled by cadence. This finding may have important implications for the interpretation of the preferred pedaling rate, especially how this is related to optimizing metabolic cost.     

The energetically optimal cadence decreases after prolonged cycling exercise

This study investigated the change in the energetically optimal cadence after prolonged cycling. The energetically optimal cadence (EOC) was determined in 14 experienced cyclists by pulmonary gas exchange at six different cadences (100–50 rpm at 10 rpm intervals). The determination of the EOC was repeated after a prolonged cycling exercise of 55 min duration, where cadence was fixed either at high (>95 rpm) or low (<55 rpm) pedalling rates. The EOC decreased after prolonged cycling exercise at a high as well as at a low fixed cadence (P < 0.01). According to the generalized muscle equations of Hill, this indicates that most likely more type I muscle fibres contribute to muscular power output after fatiguing cycling exercise compared to cycling in the beginning of an exercise bout. We suggest that the determination of EOC might be a potential non-invasive method to detect the qualitative changes in activated muscle fibres, which needs further investigation.     

Cadence and performance in elite cyclists

Many studies have attempted to describe the optimal cadence in cycling. However, the effect on performance has received little attention. The aim of the present study was therefore to examine the effect of cadence on performance during prolonged cycling (~30 min). Fourteen male elite cyclists performed two or five time trials at different cadences [60, 80, 100, 120 rpm or freely chosen cadence (FCC)]. The total work was the same between the time trials, and the subjects were instructed to complete each time trial as fast as possible by adjusting the workload with buttons mounted on the handlebar. Accumulated work and cadence was visualised on a monitor. Oxygen uptake was measured continuously and blood lactate concentration every fifth minute. Compared to 80 rpm, finishing times at 60, 100 and 120 rpm were 3.5, 1.7 and 10.2% slower (P<0.05). Finishing time at FCC (mean 90 rpm) was indistinguishable from 80 and 100 rpm. Gross efficiency at 80 rpm was 2.9, 2.3, 3.4 and 12.3% larger than at 60, FCC, 100 and 120 rpm, respectively (P<0.05). The maximal energy turnover rate was 1.7% higher at 100 than at 80 rpm (P<0.05). This could not, however, compensate for the 3.4% lower efficiency at 100 rpm. This study demonstrated that elite cyclists perform best at their most efficient cadence despite the maximal energy turnover rate being larger at a higher cadence.     

Effect of pedalling rates on physiological response during endurance cycling

This study was undertaken to examine the effect of different pedalling cadences upon various physiological responses during endurance cycling exercise. Eight well-trained triathletes cycled three times for 30 min each at an intensity corresponding to 80% of their maximal aerobic power output. The first test was performed at a freely chosen cadence (FCC); two others at FCC - 20% and FCC + 20%, which corresponded approximately to the range of cadences habitually used by road racing cyclists. The mean (SD) FCC, FCC - 20% and FCC + 20% were equal to 86 (4), 69 (3) and 103 (5) rpm respectively. Heart rate (HR), oxygen uptake (VO2), minute ventilation (VE) and respiratory exchange ratio (R) were analysed during three periods: between the 4th and 5th, 14th and 15th, and 29th and 30th min. A significant effect of time (P < 0.01) was found at the three cadences for HR, VO2. The VE and R were significantly (P < 0.05) greater at FCC + 20% compared to FCC - 20% at the 5th and 15th min but not at the 30th min. Nevertheless, no significant effect of cadence was observed in HR and VO2. These results suggest that, during high intensity exercise such as that encountered during a time-trial race, well-trained triathletes can easily adapt to the changes in cadence allowed by the classical gear ratios used in practice.     

Factors associated with the selection of the freely chosen cadence in non-cyclists

The purpose of this study was to examine both the freely chosen cadence (FCC) and the physical variables associated with cadence selection in non-cyclists. Eighteen participants pedalled at 40, 50, and 60% of their maximal power output (determined by a maximal oxygen uptake test, W _max), whilst cadence (50, 65, 80, 95, 110 rpm, and FCC) was manipulated. Gross efficiency, was used to analyse the most economical cadence whilst central and peripheral ratings of perceived exertion (RPE) were used to measure the most comfortable cadence and the cadence whereby muscle strain was minimised. Peak (T _peak), mean crank torque (T _mean) and the crank torque profile were analysed at 150 and 200 W at cadences of 50, 65, 80, 95, and 110 rpm in order to determine the mechanical load. FCC was found to be approximately 80 rpm at all workloads and was significantly higher than the most economical cadence (50 rpm). At 60% W _max, RPE peripheral was minimised at 80 rpm which coincided with the FCC. Both T _peak and T _mean decreased as cadence increased and, conversely, increased as power output increased. An analysis of the crank torque profile showed that the crank angle at both the top (DP_top) and the bottom (DP_bot) dead point of the crank cycle at 80 rpm occurred later in the cycling revolution when compared to 50 rpm. The findings suggested that the FCC in non-cyclists was more closely related to variables that minimise muscle strain and mechanical load than those associated with minimising metabolic economy.     

Cycling efficiency and pedalling frequency in road cyclists

The purpose of this study was to determine the influence of pedalling rate on cycling efficiency in road cyclists. Seven competitive road cyclists participated in the study. Four separate experimental sessions were used to determine oxygen uptake (V˙O₂) and carbon dioxide output (V˙CO₂) at six exercise intensities that elicited a V˙O₂ equivalent to 54, 63, 73, 80, 87 and 93% of maximum V˙O₂ (V˙O_2max). Exercise intensities were administered in random order, separated by rest periods of 3–5?min; four pedalling frequencies (60, 80, 100 and 120?rpm) were randomly tested per intensity. The oxygen cost of cycling was always lower when the exercise was performed at 60?rpm. At each exercise intensity, V˙O₂ showed a parabolic dependence on pedalling rate (r = 0.99–1, all P?r = 0.94–1, all P?P?P?r = 0.98, n = 6, P?r = 0.98, P?P?V˙O₂ (P?V˙O₂. These results may help us to understand why competitive cyclists often pedal at cadences of 90–105?rpm to sustain a high power output during prolonged exercise.     

Gear, inertial work and road slopes as determinants of biomechanics in cycling

In cycling the gear determines the distance travelled and the mean applied force at each leg thrust. According to Padilla et al. (J Appl Physiol 89:1522–1527, 2000), an elite cyclist was able to cycle for an hour at 14.6 m·s^–1 developing 510 W at a pedal frequency of 101 rpm. Thus, the opposing force was 34 N (=500/14.6), whereas the mean force, developed by the leg muscles, was 144.1 N. It can be calculated that in the same subject cycling on a 20% slope at the same pedal frequency, the velocity would be reduced by about 5 times, i.e. to 2.9 m·s^–1because of a fivefold increase of the opposing force. In reality, the increase of mean force developed by leg muscles is even larger, because of the fall of the cadence to 60 rpm. In general, during mountain ascents cyclists develop high forces at low cadences that are likely to be more economical; in contrast, on flat ground, they increase the pedalling rates because their aerodynamic posture does not allow high force production. The intermittent pattern of muscular force application generates speed changes that become more evident at great inclines and low cadences. It can be shown that inertial work is appreciable in cycling, increasing with the incline of the road and decreasing with the cadence. However, inertial work does not seem to affect efficiency. Differences in physiologic potential make differences in performance more evident in time trials where the mean incline of the road is not negligible. Cyclists with low body size have an advantageous force versus mass ratio in high mountain ascents.     

Interactions between cadence and power output effects on mechanical efficiency during sub maximal cycling exercises

The purpose of this study was to investigate the interactions between cadence and power output effects on cycling efficiency. Fourteen healthy subjects performed four constant power output-tests (40, 80, 120 and 160 W) in which the cadence varied in five bouts from 40 to 120 rpm. Gross efficiency (GE) was determined over the last ten respiratory cycles of each bout and was calculated as the ratio of mechanical energy to energy expenditure. Results showed that (1) GE-cadence relationships reached a maximum at each power output corresponding to the cadence maximising efficiency (CA_eff) and (2) GE increased with power output whatever the cadence until a maximal theoretical value. Moreover, interactions were found between these two factors: the cadence effect decreased linearly with power output and the power output effect increased exponentially with cadence. Consequently, cycling efficiency decreased more when cadence differed from CA_eff at low than at high power output, and increased more with power output at high cadence than at low cadence. These interactions between cadence and power output effects on GE were mainly due to cadence and power output effects on the energy expenditure shares not contributing to power production.An erratum to this article can be found at     

Comparison of office chairs with fixed forwards or backwards inclining,or tiltable seats

Summary Three adjustments of an office chair seat: — one inclining +10‡ (forwards), one inclining − 5‡ (backwards), and one being freely tiltable from −8‡ to +19.5‡ — were investigated using two groups of healthy female workers in a field (n=12), and a laboratory study (n=10), respectively. The seat adjustments were examined with regard to effects on foot swelling, lumbar muscular load, backrest pressure and subjective acceptability. Desk-work and typing were compared according to lumbar muscular activity, seat movements (tiltable seat), and backrest pressure. Foot swelling tended to increase with increasing seat height but was not influenced by the ability to tilt the seat or not. With the different seat adjustments lumbar muscular activity did not change systematically in spite of greater backrest pressure when the seat inclined backwards. The tiltable seat was preferred to the others. Typing was associated with a more constrained and tens posture than desk work, because movements, transferred to the tiltable seat, decreased and the muscular load increased. Backrest pressure was highest during typing. A tendency towards gradually increasing restlessness (i. e. seat movements) and increasing forward inclination of the tiltable seat with time was observed.     

Evidence for freely chosen pedalling rate during submaximal cycling to be a robust innate voluntary motor rhythm

Freely chosen pedalling rate during cycling represents a voluntary rhythmic movement. It is unclear to what extent this is influenced by internal (e.g. loading on the cardiopulmonary system) and external (e.g. mechanical loading) conditions. It is also unclear just how robust a voluntary motor rhythm, the freely chosen pedalling rate, actually is. The present study investigated (N = 8) whether or not the freely chosen pedalling rate during submaximal cycling was affected by separate increases in loading on the cardiopulmonary system (changed by exposure to acute simulated altitude of 3,000 m above sea level) and mechanical loading (changed by exposure to increased power output and thereby pedal force). We also investigated (N = 7) whether or not the freely chosen pedalling rate and another voluntary motor rhythm, unimanual unloaded index finger tapping rate, shared common characteristics of steadiness and individuality over a 12-week period. Results showed that the freely chosen pedalling rate was unaffected by increased loading on the cardiopulmonary system at constant mechanical loading, and vice versa. Further, the pedalling rate was steady in the longitudinal perspective (as was the tapping rate), and like tapping rate, pedalling rate was highly individual. In total this indicated that freely chosen pedalling rate primarily is a robust innate voluntary motor rhythm, likely under primary influence of central pattern generators that again are minimally affected by internal and external conditions during submaximal cycling.     

The effect of pedalling cadence on maximal accumulated oxygen deficit

Pedalling cadence influences the oxygen demand and the tolerable duration of severe intensity cycle ergometer exercise. Both of these variables are factors in the calculation of maximal accumulated oxygen deficit (MAOD), which is a widely accepted measure of anaerobic capacity. We were therefore interested in determining whether pedalling cadence affected the value of MAOD. Eighteen university students performed square wave cycling tests, using cadences of 60, 80, and 100 rev min(-1), at work rates selected to cause exhaustion in ~5 min. The oxygen demands for the tests were estimated by extrapolation from the steady-state oxygen uptake in two 4-min moderate intensity bouts performed using each cadence, and were greater at higher cadences. Times to exhaustion were shorter at higher cadences (368 ± 168 s at 60 rev min(-1) > 299 ± 118 s at 80 rev min(-1) > 220 ± 85 s at 100 rev min(-1)). These factors conflated to produce values for MAOD that were not affected by cadence (52 ± 5 ml kg(-1) = 52 ± 5 ml kg(-1) = 52 ± 5 ml kg(-1)). Similarly, the blood lactate concentrations measured 5 min post-exercise were not affected by the pedalling cadence (10.5 ± 2.1 mM = 10.8 ± 1.0 mM = 10.7 ± 2.0 mM). Although muscle contraction frequency influences many exercise responses, we conclude that the expression of anaerobic capacity is not affected by the choice of pedalling cadence.     

Power-cadence relationship in endurance cycling

In maximal sprint cycling, the power–cadence relationship to assess the maximal power output (P _max) and the corresponding optimal cadence (C _opt) has been widely investigated in experimental studies. These studies have generally reported a quadratic power–cadence relationship passing through the origin. The aim of the present study was to evaluate an equivalent method to assess P _max and C _opt for endurance cycling. The two main hypotheses were: (1) in the range of cadences normally used by cyclists, the power–cadence relationship can be well fitted with a quadratic regression constrained to pass through the origin; (2) P _max and C _opt can be well estimated using this quadratic fit. We tested our hypothesis using a theoretical and an experimental approach. The power–cadence relationship simulated with the theoretical model was well fitted with a quadratic regression and the bias of the estimated P _max and C _opt was negligible (1.0 W and 0.6 rpm). In the experimental part, eight cyclists performed an incremental cycling test at 70, 80, 90, 100, and 110 rpm to yield power–cadence relationships at fixed blood lactate concentrations of 3, 3.5, and 4 mmol L⁻¹. The determined power outputs were well fitted with quadratic regressions (R ² = 0.94–0.96, residual standard deviation = 1.7%). The 95% confidence interval for assessing individual P _max and C _opt was ±4.4 W and ±2.9 rpm. These theoretical and experimental results suggest that P _max, C _opt, and the power–cadence relationship around C _opt could be well estimated with the proposed method.     

High-frequency fatigue after alpine slalom skiing

The purpose of this study was to determine the effect of crank length and cadence on mechanical efficiency in hand cycling. Eight wheelchair dependent, high performance athletes completed four 4-min submaximal exercise bouts at a constant power output of 90 W over the different experimental conditions (crank length, pedal rate) using a sports hand bike (Draft, Godmanchester, UK). Two different crank lengths (180 and 220 mm) were tested at two different cadences (70 and 85 rev min⁻¹) using the synchronous mode of cranking. Physiological measures of oxygen uptake minute ventilation, blood lactate (B[La]), heart rate (HR), rate of perceived exertion (RPE) were recorded, gross (GE) and net (NE) efficiency were calculated. A two-way ANOVA with repeated measures was applied to determine the effects of crank length, cadence and their interaction on these physiological measures. Both GE and NE were significantly higher and significantly lower for the 180 mm crank (P < 0.05). No significant main effect was found for cadence on the physiological measures (P > 0.05). Likewise, no interactions between crank length and pedal rate were found. There was however, a trend observed with HR and B[La] often lower with the 180 mm crank, indicating lower physiological stress. The RPE data supported this finding, with a tendency for lower ratings with the 180 mm crank (9 ± 2 vs. 10 ± 3). The short crank length when used at 85 rev min⁻¹ was found to be the most efficient (GE 21.4 ± 3.1%). In conclusion, crank length has a significant effect on ME in hand cycling. A shorter crank length of 180 mm was found to be more efficient than the 220 mm, regardless of pedal rate during hand cycling.     

Relationship between the increase of effectiveness indexes and the increase of muscular efficiency with cycling power

We determined the index of effectiveness (IE), as defined by the ratio of the tangential (effective force) to the total force applied on the pedals, using a new method proposed by Mornieux et al. (J Biomech, 2005), while simultaneously measuring the muscular efficiency during sub-maximal cycling tests of different intensities. This allowed us to verify whether part of the changes in muscular efficiency could be explained by a better orientation of the force applied on the pedals. Ten subjects were asked to perform an incremental test to exhaustion, starting at 100 W and with 30 W increments every 5 min, at 80 rpm. Gross (GE) and net (NE) efficiencies were calculated from the oxygen uptake and W _Ext measurements. From the three-dimensional force’s measurements, it was possible to measure the total force (F _Tot), including the effective (F _Tang) and ineffective force (F _Rad+Lat). IE has been determined as the ratio between F _Tang and F _Tot, applied on the pedals for three different time intervals, i.e., during the full revolution (IE_360°), the downstroke phase (IE_180°Desc) and the upstroke phase (IE_180°Asc). IE_360° and IE_180°Asc were significantly correlated with GE (r=0.79 and 0.66, respectively) and NE (r=0.66 and 0.99, respectively). In contrast, IE_180°Desc was not correlated to GE or to NE. From a mechanical point of view, during the upstroke, the subject was able to reduce the non-propulsive forces applied by an active muscle contraction, contrary to the downstroke phase. As a consequence, the term ‘passive phase’, which is currently used to characterize the upstroke phase, seems to be obsolete. The IE_180°Asc could also explain small variations of GE and NE for a recreational group.     

The most economical cadence increases with increasing workload

Several studies have suggested that the most economical cadence in cycling increases with increasing workload. However, none of these studies have been able to demonstrate this relationship with experimental data. The purpose of this study was to test the hypothesis that the most economical cadence in elite cyclists increases with increasing workload and to explore the effect of cadence on performance. Six elite road cyclists performed submaximal and maximal tests at four different cadences (60, 80, 100 and 120 rpm) on separate days. Respiratory data was measured at 0, 50, 125, 200, 275 and 350 W during the submaximal test and at the end of the maximal test. The maximal test was carried out as an incremental test, conducted to reveal differences in maximal oxygen uptake and time to exhaustion (short-term performance) between cadences. The results showed that the lowest oxygen uptake, i.e. the best work economy, shifted from 60 rpm at 0 W to 80 rpm at 350 W (P<0.05). No difference was found in maximal oxygen uptake among cadences (P>0.05), while the best performance was attained at the same cadence that elicited the best work economy (80 rpm) at 350 W (P<0.05). This study demonstrated that the most economical cadence increases with increasing workload in elite cyclists. It was further shown that work economy and performance are related during short efforts (~5 min) over a wide range of cadences.     

Effect of cycling position on oxygen uptake and preferred cadence in trained cyclists during hill climbing at various power outputs

Numerous researchers have studied the physiological responses to seated and standing cycling, but actual field data are sparse. One open issue is the preferred cadence of trained cyclists while hill climbing. The purpose of this study, therefore, was to examine the affect of cycling position on economy and preferred cadence in trained cyclists while they climbed a moderate grade hill at various power outputs. Eight trained cyclists (25.8 ± 7.2 years, 68.8 ± 5.0 ml kg⁻¹ min⁻¹, peak power 407.6 ± 69.0 W) completed a seated and standing hill climb at approximately 50, 65 and 75% of peak power output (PPO) in the order shown, although cycling position was randomized, i.e., half the cyclists stood or remained seat on their first trial at each power output. Cyclists also performed a maximal trial unrestricted by position. Heart rate, power output, and cadence were measured continuously with a power tap; ventilation , BF and cadence were significantly higher with seated climbing at all intensities; there were no other physiological differences between the climbing positions. These data support the premise that trained cyclists are equally economical using high or low cadences, but may face a limit to benefits gained with increasing cadence.     

Efficiency in cycling: a review

We focus on the effect of cadence and work rate on energy expenditure and efficiency in cycling, and present arguments to support the contention that gross efficiency can be considered to be the most relevant expression of efficiency. A linear relationship between work rate and energy expenditure appears to be a rather consistent outcome among the various studies considered in this review, irrespective of subject performance level. This relationship is an example of the Fenn effect, described more than 80 years ago for muscle contraction. About 91% of all variance in energy expenditure can be explained by work rate, with only about 10% being explained by cadence. Gross efficiency is strongly dependent on work rate, mainly because of the diminishing effect of the (zero work-rate) base-line energy expenditure with increasing work rate. The finding that elite athletes have a higher gross efficiency than lower-level performers may largely be explained by this phenomenon. However, no firm conclusions can be drawn about the energetically optimal cadence for cycling because of the multiple factors associated with cadence that affect energy expenditure.     

The between and within day variation in gross efficiency

Before the influence of divergent factors on gross efficiency (GE) [the ratio of mechanical power output (PO) to metabolic power input (PI)] can be assessed, the variation in GE between days, i.e. the test–retest reliability, and the within day variation needs to be known. Physically active males (n = 18) performed a maximal incremental exercise test to obtain VO_2max and PO at VO_2max (PVO_2max), and three experimental testing days, consisting of seven submaximal exercise bouts evenly distributed over the 24 h of the day. Each submaximal exercise bout consisted of six min cycling at 45, 55 and 65% PVO_2max, during which VO₂ and RER were measured. GE was determined from the final 3 min of each exercise intensity with: GE = (PO/PI) × 100%. PI was calculated by multiplying VO₂ with the oxygen equivalent. GE measured during the individually highest exercise intensity with RER <1.0 did not differ significantly between days (F = 2.70, p = 0.08), which resulted in lower and upper boundaries of the 95% limits of agreement of 19.6 and 20.8%, respectively, around a mean GE of 20.2%. Although there were minor within day variations in GE, differences in GE over the day were not significant (F = 0.16, p = 0.99). The measurement of GE during cycling at intensities approximating VT is apparently very robust, a change in GE of ~0.6% can be reliably detected. Lastly, GE does not display a circadian rhythm so long as the criteria of a steady-state VO₂ and RER <1.0 are applied.     

Work and power outputs determined from pedalling and flywheel friction forces during brief maximal exertion on a cycle ergometer

Work and power outputs during short-term, maximal exertion on a friction loaded cycle ergometer are usually calculated from the friction force applied to the flywheel. The inertia of the flywheel is sometimes taken into consideration, but the effects of internal resistances and other factors have been ignored. The purpose of this study was to estimate their effects by comparing work or power output determined from the force exerted on the pedals (pedalling force) with work or power output determined from the friction force and the moment of inertia of the rotational parts. A group of 22 male college students accelerated a cycle ergometer as rapidly as possible for 3 s. The total work output determined from the pedalling force (TW _p) was significantly greater than that calculated from the friction force and the moment of inertia (TW _f). Power output determined from the pedalling force during each pedal stroke (SP_p) was also significantly greater than that calculated from the friction force and the moment of inertia. Percentage difference (%diff), defined by %diff = {(TW _p − TW_f/TW _f} × l00, ranged from 16.8 % to 49.3 % with a mean value of 30.8 (SD 9.1)%. It was observed that %diff values were higher in subjects with greaterTW _p or greater maximalSP _p. These results would indicate that internal resistances and other factors, such as the deformation of the chain and the vibrations of the entire system, may have significant effects on the measurements of work and power outputs. The effects appear to depend on the magnitudes of pedalling force and pedal velocity.