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Maximal oxygen uptake (V[O.sub.2]max) is an important indicator of health-risk status, specifically for coronary heart disease (Blair et al., 1989). Direct measurement of V[O.sub.2]max is considered to be the most accurate means of determining cardiovascular fitness level. Typically, this measurement is taken using a progressive exercise test on a treadmill or cycle ergometer. Unfortunately, this test is costly and time consuming and requires a well equipped laboratory, highly trained personnel, and for some populations medical supervision. Therefore, submaximal exercise test protocols that predict V[O.sub.2]max have been developed (Astrand & Rhyming, 1954; Fitchett, 1985). These tests require less equipment, time and are easily administered without highly skilled personnel.

Examined the physiological responses of elderly Japanese women to a well-rounded exercise program performed in water. Results indicated that the 12-week program elicited significant improvements in intervention group women's cardiorespiratory fitness, muscular strength, agility, flexibility, body fat, and total cholesterol. Water-based exercise appeared to be very safe and beneficial to the participants. (SM)

To investigate sprinting strategy, acceleration and velocity patterns were determined in college football players (n = 61) during performance of a 9.1-, 36.6-, and 54.9-m sprints. Acceleration and velocity were determined at 9.1-m intervals during each sprint. Lower-body strength and power were evaluated by 1 repetition maximum (1-RM) squat, power clean, jerk, vertical jump, standing long jump, and standing triple jump. Sprint times averaged 1.78 [+ or -] 0.11 seconds (9.1 m), 5.18 [+ or -] 0.35 seconds (36.6 m), and 7.40 [+ or -] 0.53 seconds. Acceleration peaked at 9.1 m (2.96 [+ or -] 0.44 m x [s.sup.-2]), was held constant at 18.3 m (3.55 [+ or -] 0.0.94 m x [s.sup.-2]), and was negative at 27.4 m (-1.02 [+ or -] 0.72 m x [s.sup-2]). Velocity peaked at 18.3 m (8.38 [+ or -] 0.65 m x [s.sup.-1]) and decreased slightly, but significantly at 27.4 m (7.55 [+ or -] 0.66 m x [s.sup.-1]), associated with the negative acceleration. Measures of lower-body strength were significantly related to acceleration, velocity, and sprint performance only when corrected for body mass. Lower-body strength/ BM and power correlated highest with 36.6-m time (rs = -0.55 to -0.80) and with acceleration (strength r = 0.67-0.49; power r = 0.73-0.81) and velocity (strength r = 0.68-0.53; power r = 0.74-0.82) at 9.1 m. Sprint times and strength per body mass were significantly lower in lineman compared with linebackers-tight ends and backs. The acceleration and velocity patterns were the same for each position group, and differences in sprint time were determined by the magnitude of acceleration and velocity at 9.1 and 18.3 m. Sprint performance in football players is determined by a rapid increase in acceleration (through 18.3 m) and a high velocity maintained throughout the sprint and is independent of position played. The best sprint performances (independent of sprint distance) appear to be related to the highest initial acceleration (through 18.3 m) and highest attained and maintained velocity. Strength relative to body mass and power appears to impact initial acceleration and velocity (through 18.3 m) in contribution to sprint performance. KEY WORDS 40-yd spring, body mass, acceleration, muscular strength, muscular power, performance

The purpose of this study was to determine the difference between hand and electronic timing of 40-yd dashes in college football players. National Collegiate Athletic Association Division II players (n = 59) were measured during a 40-yd sprint by electronic timing and simultaneously by 7 experienced hand timers using digital stopwatches. Electronic times were initiated by lifting the hand from a switch mat and stopped by the torso passing through an infrared beam. Hand timers initiated timing on first movement of the player from a 3-point stance. To establish performance and timing reliabilities, 32 players completed a second trial. Interrater reliability for hand timing was intraclass correlation coefficient (ICC) = 0.987 (p < 0.001). Five of the 7 timers did not differ significantly (p > 0.05) in their timing. The maximum difference among the hand timers on any given trial was 0.19 [+ or -] 0.14 seconds, with a 95% confidence interval (CI) of -0.08 to 0.41 seconds. Hand timing (4.85 [+ or -] 0.28 seconds) was significantly faster (p < 0.001) than electronic timing (5.16 [+ or -] 0.28 seconds), producing an average difference of 0.31 [+ or -] 0.07 seconds (6.0 [+ pr -] 1.3%) and a 95% CI on the average difference of 0.44 to 0.18 seconds. The correlation between electronic timing and hand timing was ICC = 0.985 (p < 0.001). Practically speaking, electronic timing produces the best measurement of 40-yd dash speed, and using the hand timing produces consistently but significantly faster times. KEY WORDS sprint timing, sprinting, reliability

The purpose of this study was to assess changes in upper-body muscular strength and work capacity following off-season resistance training and the resultant effect on prediction of muscular strength (1 repetition maximum, or 1 RM). National Collegiate Athletic Association (NCAA) Division II football players (n = 58) were divided into low-strength (LS, 1RM 85% 1RM) than at higher repetitions (>6RM, [less than or equal to] 80% 1RM) at both pre-and post-training. In conclusion, changes in muscular strength associated with the off-season training program used herein appear to have little effect on work capacity or prediction of 1RM using submaximal loads. For repetition predictions to accurately track changes following resistance training, the test load must be relatively high (>85% 1RM) and the repetitions low ([less than or equal to] 5 reps). KEY WORDS off-season conditioning, performance evaluation, bench press