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No study has assessed supramaximal (over 100% 1RM) back squat variations as a potentiating stimulus in collegiate throwers. The purpose of this study was to test the hypothesis that a supramaximal Anderson (bottom-up) quarter squat potentiating stimulus would improve discus throw performance in Division I throwers compared to a dynamic warm-up alone. Nine NCAA division I thrower athletes (age: 20.1±1.4 years; 1RM back squat/body weight: 2.5±0.4 kg) randomly completed two sessions separated by at least 72 hours. One session involved a standardized dynamic warm-up alone (DyWU) followed by three trials of maximal discus throwing. The other session involved a dynamic warm-up with a supramaximal (105% 1RM) Anderson (bottom-up) quarter-squat set of 5 repetitions post activation performance enhancement stimulus (DyWU+PAPE) followed by three trials of maximal discus throwing. A two-way (warm-up strategy x time) ANOVA with repeated measures for each time point was used, with significance set at p< 0.05. There were no significant (p> 0.05) differences between DyWU alone versus DyWU+PAPE stimulus for discus throw distances at either 8 min. (31.7±5.6 vs 30.6±6.5 meters, respectively; d = -0.18), 11 min. (33.4±3.6 vs 31.3±4.7 meters, respectively; d = -0.52), or 14 min. post warm-up (34.1±3.9 vs 32.3±5.3 meters, respectively; d = -0.40). Compared to a dynamic warm-up alone, supramaximal Anderson quarter-squats following a dynamic warm-up had trivial/small to moderate detrimental effects on discus throw performance between 8-14 minutes post stimuli in Division I trained throwers, likely due to excess fatigue/PAPE inhibition.

The effect of heavy metals on microbial respiration in organic materials used as soil amendments was evaluated to assess the stability of the materials. Solutions of Pb (II), Cu (II) and Zn (II) at rates of 5, 10 and 50mg metal g(-1) were added to green waste compost, peat, coir and wood bark. Metal toxicity led to a significant decrease in carbon dioxide evolved by the contaminated materials, up to 80% less at the highest rate of addition compared to the untreated material. There was a significant negative correlation between the organic carbon content of an amendment and the inhibition of CO(2) evolution by all three heavy metals. There was also a significant negative correlation between an amendment's cation exchange capacity and the inhibition of CO(2) evolution caused by Cu and Zn. The ability of the organic materials to enhance respiration in a soil from the vicinity of a Pb/Zn mine was also evaluated, by applying them to the soil at rates of 1, 10 and 20%. CO(2) evolution from the contaminated soil was enhanced significantly by the addition of all of the amendments, with coir causing up to 90% enhancement at high levels of addition., (Copyright © 2010 Elsevier B.V. All rights reserved.)