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Observations of athletes in seated and standing cycling positions in laboratory and field settings have led to the perception that they produce different outputs. The purpose of this study was to determine whether there are differences in power output and physiological responses between seated and standing positions of athletes during 3 consecutive Wingate tests. Seven (n = 7) elite-level speedskaters completed 3 x 30-second Wingate tests (resistance = 7.5% body weight) with 3.5 minutes of recovery between each test in both seated and standing positions. During the recovery period, athletes pedaled against no resistance in the seated position. Testing was randomized and separated by at least 48 hours. Power output, heart rate, blood lactate, and muscle oxygenation data were collected. Statistical analysis of comparable tests (i.e., seated Wingate test 1 [WinD1] compared with standing Wingate test 1 [WinU1]; WinD2:WinU2; WinD3:WinU3) revealed no significant differences between the seated and standing variables. Position during a short-duration maximal-effort exercise test on a stationary bike did not produce statistically different results in power, maximal heart rate, blood lactate, or muscle oxygenation. As no differences were detected between positions, practitioners can allow subjects to choose their position. Also, if a subject rises out of the seat during a "seated" test, this change may not affect the subject's physiological variables. However, transitioning from one position to the other during the test is not advised due to the possible chance of injury. It should be acknowledged that there may be reasons for stipulating one position over another (e.g., injuries, leg length).

Low muscle glycogen levels due to consecutive days of extensive exercise have been shown to cause fatigue and thus decrements in performance. Low muscle glycogen levels could also lead to oxidation of the branched chain amino acids and central fatigue. Therefore, the questions become, can low muscle glycogen not only lead to peripheral and central fatigue but also to overtraining, and if so can overtraining be avoided by consuming sufficient quantities of carbohydrates? Research on swimmers has shown that those who were nonresponsive to an increase in their training load had low levels of muscle glycogen and consumed insufficient energy and carbohydrates. However, cyclists who increased their training load for 2 wk but also increased carbohydrate intake to maintain muscle glycogen levels still met the criteria of over-reaching (short-term overtraining) and might have met the criteria for overtraining had the subjects been followed for a longer period of time. Thus, some other mechanism than reduced muscle glycogen levels must be responsible for the development and occurrence of overtraining.

The purpose of this study was to determine if consumption of appropriate amounts of carbohydrate during a period of increased exercise training would protect the athletes from becoming overtrained. Eight male competitive cyclists were monitored and tested during three training periods: a) normal training (moderate intensity, long duration, 7 d, NORM); b) overtraining (high intensity training, 15 d, OVER); and c) recovery (minimal training, 6 d, REC). Throughout the training 160 g of liquid carbohydrate were consumed within the first 2 h after the daily exercise bout. Mean dietary intake (NORM = 13.7 +/- 1.6, OVER = 14.1 +/- 1.0 MJ.d-1) and carbohydrate percent (NORM = 64.0 +/- 2.1, OVER = 67.4 +/- 2.5%) were not different during the different training periods. Similarly, resting muscle glycogen levels were not different (NORM = 530.9 +/- 42.5, OVER = 571.2 +/- 27.5 mumol.g-1 dry weight). Five criteria were used to determine if overtraining occurred in a subject (decreased maximal workload, maximal heart rate, ratio of maximal lactate to rating of perceived exertion (HLa:RPE), and resting plasma cortisol levels, increased affirmative response to a daily questionnaire). All subjects met at least three of the five criteria and thus were classified as overtrained. Therefore, short-term overtraining may occur even when resting muscle glycogen levels are maintained.

Despite interest in competitive strategy by coaches and athletes, there are no systematically collected data regarding the effect of differences in pacing strategy on the outcome of middle distance (2-4 min duration) events. In this study different pacing strategies were evaluated using a 2-km time trial on a bicycle attached to a wind load simulator. Well-trained subjects (N = 9) performed five separate time trials with the pace during the first 50% of the trial experimentally constrained within the usual real world range from very slow (approximately 55% of best time) to very fast (approximately 48% of best time). Serial VO2 was measured to estimate the oxidative contributions to the trial and accumulated O2 deficit and postexercise blood lactate measured to estimate the anaerobic contribution to the trial. The evenly paced trial (first 1 km = 50.9% final time) produced the fastest total time. The starting pace to final time relationship was described by a U shaped second order polynomial curve with the nadir for final time at a starting pace of 51% of best total time. There were no systematic differences in serial VO2, accumulated O2 deficit, or postexercise lactate that could account for the pacing related variations in performance. The data support the concept of relatively even pacing in middle distance events with negative consequences for even small variations in this strategy.

A comparison of the physiological responses to in-line skating with the more traditional modes of exercise training has not been reported. The purpose of this study was to examine the physiological responses to in-line skating compared with running and cycling. Nine trained volunteers (2 male, 7 female) performed 3-6 submaximal (30-90% VO2max) workloads with each exercise mode. Oxygen uptake, heart rate and blood lactate were measured during each trial. Across the spectrum of oxygen uptakes studied, heart rate was higher with in-line skating than with cycling or running. At a lactate concentration of 4 mM, oxygen uptake was less for in-line skating and cycling than for running. Therefore, while in-line skating may be an effective mode of aerobic exercise, the training adaptations for in-line skating at 4 mM lactate may not be as great as for running, and at a given HR may be less than for running and cycling.

To study the physiological response to heavy training, seven male competitive cyclists intensified their normal training program for two weeks (IIT) in order to achieve a state of short-term overtraining. The subjects underwent a graded cycle ergometer test to exhaustion, an outdoor 8.5 km time trial and a computerized test to study reaction time and visual perception, before, during and after the two weeks of intensified training and after two weeks of recovery. Furthermore subjects kept a daily log in the form of a questionnaire. After two weeks of IIT all subjects showed symptoms of overtraining: the general state of well being declined as indicated by the questionnaire while performances on time trial (mean +/- SEM: 830 +/- 14 sec-871 +/- 19 sec), contests and maximal power output (mean +/- SEM: 336 7 watt-310 +/- 5 watt) declined significantly. Maximal (mean +/- SEM 11.8 +/- 1.1 mmol.l-1-5.9 +/- 0.5 mmol.l-1) and submaximal lactate values were significantly lowered during ergometer test after the IIT, while the workload at the 4 mmol point increased significantly (mean +/- SEM 234 +/- 10 watt-267 +/- 13 watt). Sleeping heart rate increased significantly (mean +/- SEM 49.5 +/- 9.3 BPM-54.3 +/- 8.8 BPM). Maximal heart rate (mean +/- SEM 185 +/- 3 BPM-178 +/- 2 BPM, mean heart rate during the time trial (mean +/- SEM 178 +/- 2 BPM-169 +/- 2 BPM) and VO2max (mean +/- SEM 4801 +/- 121 ml.min-1-4409 +/- 101 ml.min-1) were all significantly lowered by the IIT.(ABSTRACT TRUNCATED AT 250 WORDS)

In order to determine the ventilatory threshold (VT) and the lactate threshold (LT) in a reliable way, a new method is proposed and compared with conventional methods. The new method consists of calculating the point that yields the maximal distance from a curve representing ventilatory and metabolic variables as a function of oxygen uptake (VO2) to the line formed by the two end points of the curve (Dmax method). Male cyclists (n = 8) performed two incremental exercise tests a week apart. Ventilatory/metabolic variables were measured and blood was sampled for later lactate measurement during each workload and immediately after exercise. No statistical differences were observed in the threshold values (expressed as absolute oxygen uptake; VO2) determined by the Dmax method and the conventional linear regression method (according to O2 equivalent; EqO2) and venous blood at the onset of blood lactate (OBLA), while VT assessed with the conventional linear method (according to the slope of CO2 output; Vslope) yielded significantly lower threshold values. Similar results were obtained from the reproducibility test. Thus, the Dmax method appears to be an objective and reliable method for threshold determination, which can be applied to various ventilatory or metabolic variables yet yield similar results. The results also showed that breathing frequency can be used to determine VT.