Strategies that reduce the physiological load during the cycling phase of triathlon events may enable athletes to perform better during the subsequent running phase. The current study examines the effects of changes in shoe cleat position, during the cycling phase of a simulated duathlon, on running performance of competitive triathletes. Controlled crossover. 12 triathletes completed a simulated duathlon race using either their normal (control) cycling cleat position or an experimental mid-foot (arch) shoe cleat position. The duathlon consisted of a 30-min cycle, completed at 65% of the athlete’s previously determined peak aerobic power output, followed by a self-paced maximal effort 5.5-km treadmill run. Respiratory-gas measurements were made throughout testing using an automated online metabolic system. There were only trivial differences between conditions for any metabolic variables obtained during the cycling phase of the duathlon. However run time following the mid-foot condition was 2.2% (90% CI 0.8-3.6%) shorter compared to the control condition. In addition Oxygen consumption during the run phase was greater following the mid-foot condition by 2.2% (-0.5-5.1%). We conclude that worthwhile performance gains can be achieved during the running phase of a duathlon when athletes utilize a mid-foot-cleat shoe position during the cycling phase of an event. The improvement in running performance was likely due to a reduction in the rate of plantar flexor muscle fatigue during the cycling phase of the event.

The aims of this study were (i) to investigate the participation in Triple Iron ultra-triathlons covering 11.4 km swimming, 540 km cycling, and 126.6 km running between 1988 and 2011 and (ii) to analyze the nationalities of the athletes achieving the fastest swimming, cycling, running and overall race times. Six out of seven races worldwide were held in Europe. Participation of male Triple Iron ultra-triathlons increased over the 24-year period while the participation of females remained stable at ~8% of the total field. Out of the 1,258 participants, 1.077 athletes (85.6%) originated from Europe. The number of male European athletes (r2 = 0.23; P = 0.02) and male North American athletes (r2 = 0.35; P less than 0.01) increased across years. European males (2.161±168.5 min) were faster (P less than 0.05) than both European females (2.615±327.2 min) and North American males (2.850±370.6 min). Male European athletes improved (r2 = 0.18; P = 0.043), while European females impaired (r2 = 0.48; P = 0.001) overall race time. To summarize, participation in Triple Iron ultra-triathlon increased across years where most of the participants originated from Europe. European males achieved the fastest overall race times and improved their performance across years. Future studies need to investigate what motivates these athletes to compete in these races.

High compressive load applied to the patellofemoral joint at great knee flexion angle (e.g. >60º of flexion), as usually observed in cycling may provide a link between body position on the bicycle and knee joint forces. The aim of the present study was to compare knee joint forces in different saddle heights. Right pedal force and lower limb kinematics were collected for 24 competitive cyclists and triathletes at self-selected preferred, high (-10º of knee flexion angle from preferred), low (+10º of knee flexion angle from preferred) and optimal (25º of knee flexion angle) saddle heights in submaximal pedalling cadence and workload trials (3.45 ± 0.6 W/kg, 90 ± 2 rpm and 163 ± 33 J). Patellofemoral compressive and tibiofemoral anterior-posterior and compressive force were computed by inverse dynamics and compared for different saddle heights via effect sizes. Patellofemoral compressive force (5-13%) and tibiofemoral compressive force (1-7%) were not substantially affected by changes in saddle height. Tibiofemoral anterior shear force decreased at low saddle heights (4-6% of the preferred height) compared to optimal (35%) and high saddle heights (53%). Greater knee flexion angles were observed for lower saddle heights (8-34%). Knee flexion angle was significantly affected by changes in saddle height, which may indicate that using joint kinematics to assess saddle height effects may be useful to anticipate overload in knee joint.

Many different methods of simulating triathlon performance in controlled conditions have been developed without establishing the reliability of these assessments. The aim of this study was to determine the reliability of performance and physiological measures during simulated triathlon. Seven trained male triathletes completed initial familiarization, followed by three separate simulated sprint-distance triathlon trials (750 m swim, 500 kJ bike, 5 km run), using a 25 m pool, an electromagnetically braked cycle ergometer and motorized treadmill. Performance (time and mean cycling power) and physiological variables (oxygen uptake, ventilation, heart rate and blood lactate concentration) were measured throughout. Reliability between trials was assessed using one-way analysis of variance (ANOVA), coefficient of variation (CV), intraclass correlation coefficient (ICC) and ratio limits of agreement (LoA). No significant differences were found in performance or physiological variables measured across simulated triathlon trials. High levels of reliability (CV less than 10% and="" ICC="" > 0.8) were observed for all performance measures (except transitions) and a majority of physiological variables. Measurement of blood lactate concentration displayed the poorest reliability throughout, with CV’s up to 17.3% and ICC’s as low as 0.4. Ratio LoA for total performance time were similar between trials 1-2 (1.008 */÷ 1.077) and trials 2-3 (1.004 */÷ 1.064). Based on these results simulated sprint-distance triathlon allows for reliable measurement of performance parameters and associated physiological responses in a controlled environment. This reliability data should be considered by simulated triathlon studies when determining statistical power and sample sizes, to allow for more rigorous detection of genuine changes between trials.

Editorial. Looking for the “Athlete 2.0”: a collaborative challenge.

Efficiency, the ratio of work generated to the total metabolic energy cost, has been suggested to be a key determinant of endurance cycling performance. The purpose of this brief review is to evaluate the influence of gross efficiency on cycling power output and to consider whether or not gross efficiency can be modified. In a re-analysis of data from five separate studies, variation in gross efficiency explained ~30% of the variation in power output during cycling time-trials. Whilst other variables, notably VO2max and lactate threshold, have been shown to explain more of the variance in cycling power output, these results confirm the important influence of gross efficiency. Case study, cross-sectional, longitudinal, and intervention research designs have all been used to demonstrate that exercise training can enhance gross efficiency. Whilst improvements have been seen with a wide range of training types (endurance, strength, altitude), it would appear that high intensity training is the most potent stimulus for changes in gross efficiency. In addition to physiological adaptations, gross efficiency might also be improved through biomechanical adaptations. However, ‘intuitive’ technique and equipment adjustments may not always be effective. For example, whilst ‘pedalling in circles’ allows pedalling to become mechanically more effective, this technique does not result in short term improvements in gross efficiency.