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Since interest in science classes has declined recently and obesity, especially in youth, continues to increase, an exercise physiology-based course was taught in public parks to promote active-learning science and healthy living. The course emphasized and integrated exercise, nutrition, and health during a 3-h session. Following an introduction, five hands-on laboratory-based student modules were performed. Students performed respiratory, cardiovascular, temperature regulation, energy expenditure, oxygen uptake, and exercise modules. During most modules, the students made measurements at rest and during the performance of exercise at different intensities. The students were very involved and engaged in problem solving throughout the session. The program was given for 10 days to more than 500 students representing 18 classes from 10 different schools. Evaluations indicated that the program was a real-life science experience that gave the students a new understanding of how their bodies worked and the purpose of exercise. The students and teachers also experienced "school learning" put into action as the program fit well with their science curriculum.

Maximal steady state (MSS) speed can be determined from blood lactate concentration (HLa); however, this method is not optimal. The purpose of this study was to determine whether near-infrared spectroscopy (NIRS) technology could be used to detect a breakpoint in percent oxygen saturation (St[O.sub.2]) of the muscle and whether the determined breakpoint exercise intensity could be used to determine MSS exercise intensity. Sixteen distance runners and triathletes (men = 9, V[O.sub.2]max = 64.9 [+ or -] 4.9 ml x [kg.sup.-1] x [min.sup.-1], women = 7, V[O.sub.2]max = 50.8 [+ or -] 7.0 ml x [kg.sup.-1]. [min.sup.-1]) completed an incremental exercise test. A change from linearity when plotting St[O.sub.2] or HLa vs. running speed was defined as the breakpoint. The subjects then completed constant speed runs to determine maximal lactate steady state (MLSS). In 12 subjects, breakpoints were identified for both HLa and St[O.sub.2] values. Predicted MLSS velocities from HLa breakpoint (12.76 [+ or -] 1.63 km x [h.sup.-1]), St[O.sub.2] breakpoint (12.84 [+ or -] 1.58 km x [h.sup.-1]), and 4 mM HLa (13.49 [+ or -] 1.71 km x [h.sup.-1]) methods from the incremental test did not differ from MLSS speeds (13.04 [+ or -] 2.03 km x [h.sup.-1]). A Bland and Altman analysis of agreement between the MLSS and the St[O.sub.2] breakpoint speeds resulted in a mean difference of 0.14 [+ or -] 0.36, whereas the mean difference between MLSS and HLa breakpoint speeds was 0.19 [+ or -] 0.43. During the incremental test, no St[O.sub.2] breakpoint was determined in 2 subjects, whereas 2 subjects had no HLa breakpoint. The results of this study lead us to conclude that the NIRS determination of St[O.sub.2] is a noninvasive technique that is comparable with HLa in determining MSS intensity and therefore appropriate for use in determining exercise training intensity. KEY WORDS lactate threshold, training, endurance exercise, running

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). KEY WORDS anaerobic power, cycling, cycling position, exercise position, power output, muscle oxygenation

A study assessed the influence of the long lying, the bent knee, the vertical leg crunch, and the leg raise exercises on muscular activity of the rectus abdominis. Four male subjects had surface electrodes placed on the 4 quadrants of the rectus abdominis, one of which was assumed to be influenced by the exercises. Analyses of electromyographic (EMG) recordings proved that none of the exercises strengthened the individual muscle quadrants.