Bryce M. Abbey

Walking to School: Taking Research to Practice.

JOPERD • Volume 79 No. 6 • August 2008 A lthough walking to and from school, up hill both ways, was once the norm among school children in the United States, children’s and parents’ perceptions are different today. Biking and walking to and from school are no longer considered normal activities, as only 23 percent of children ages fi ve to 15 bike or walk to and from school (Toor & Havlick, 2004). To many children, it is normal to load up in the family car, drive a few blocks to wait in line behind dozens of other cars, inching along until they are within a few feet of the school, and then hop out near the front entrance. For parents, this morning routine is usually repeated in the afternoon. Why? Is it safer than letting children walk to school? The vehicle congestion in front of the school caused by this daily routine increases the risk of a vehicle-pedestrian accident and increases neighborhood safety concerns. Unfortunately, this has become “normal.”

Oxygen Consumption, Heart Rate, and Blood Lactate Responses to an Acute Bout of Plyometric Depth Jumps in College-aged Men and Women

Brown, GA, Ray, MW, Abbey, BM, Shaw, BS, and Shaw, I. Oxygen consumption, heart rate, and blood lactate responses to an acute bout of plyometric depth jumps in college-aged men and women. J Strength Cond Res 24(9): 2475-2482, 2010-Although plyometrics are widely used in athletic conditioning, the acute physiologic responses to plyometrics have not been described. The purpose of this study was to investigate the oxygen consumption, heart rate, and blood lactate responses to a single session of plyometric depth jumps. Twenty recreationally trained college-aged subjects (10 men, 10 women) participated in a single session of 8 sets of 10 box depth jumps from a height of 0.8 m with 3 minutes of passive recovery between each set. Plyometric depth jumping elicited 82.5 ± 3.1% and 77.8 ± 3.1% of the measured maximal oxygen consumption (O2max) for women and men, respectively, with no difference in oxygen consumption in ml/kg/min or percent O2max between sexes or sets. Heart rate significantly increased (p < 0.05) from 68.1 ± 2.9 beats·min−1 at rest to 169.6 ± 1.2 beats·min−1 during depth jumping. Sets 5 to 8 elicited a higher (p < 0.05) heart rate (173.3 ± 1.3 beats·min−1) than sets 1 to 4 (164.6 ± 1.8 beats·min−1). Women exhibited a higher heart rate (p < 0.05) during sets 1 and 2 (169.9 ± 2.8 beats·min−1) than men (150.7 ± 4.4 beats·min−1). The blood lactate concentrations were significantly (p < 0.05) increased above resting throughout all sets (1.0 ± 0.2 mmol·L−1 compared with 2.9 ± 0.1 mmol·L−1), with no differences between sexes or sets. Plyometric depth jumping significantly increased oxygen consumption, heart rate, and blood lactate in both men and women, but no significant difference was found between the sexes. Plyometric depth jumping from a height of 0.8 m has similar energy system requirements to what Wilmore and Costill termed “Aerobic Power” training, which should enhance O2max, lactate tolerance, oxidative enzymes, and lactate threshold.

Validity of HydraTrend Reagent Strips for the Assessment of Hydration Status

Abstract Abbey, BM, Heelan, KA, Brown, GA, and Bartee, RT. Validity of HydraTrend reagent strips for the assessment of hydration status. J Strength Cond Res 28(9): 2634–2639, 2014—Hydration is used by athletic governing organizations for weight class eligibility. The measurement of urine specific gravity (USG) as a measure of hydration by reagent strips is a controversial issue. The purpose of this study was to determine the validity of HydraTrend reagent strips that facilitate the correction of USG for alkaline urine samples against refractometry for the assessment of USG. Fifty-one participants (33 males, age = 22.3 ± 1.3 years; 18 females, age = 22.4 ± 1.2 years) provided 84 urine samples. The samples were tested for USG using refractometry and reagent strips and for pH using reagent strips and a digital pH meter. Strong correlation coefficients were found between refractometry and reagent strips for USG (rs(82) = 0.812, p < 0.01) and between reagent strips and pH meter for pH (rs(82) = 0.939, p < 0.01). It was observed that false negative results for National Collegiate Athletic Association (NCAA) requirements (fail refractometry with USG >1.020, pass reagent strips with USG ⩽1.020) occurred 39% (33/84) of the time and false negative results for National Federation of State High School Association (NFHS) requirements (fail refractometry with USG >1.025, pass reagent strips with USG ⩽1.025) occurred 14% (12/84) of the time. There were no false positives (pass refractometry and fail reagent strips) for NCAA or NFHS requirements. These data show that refractometry and reagent strips have strong positive correlations. However, the risk of a false negative result leading to incorrect certification of euhydration status outweighs the benefits of the HydraTrend reagent strips for the measurement of USG.