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Purpose:To investigate the intersession reliability of selected kinematic and kinetic variables during countermovement vertical jumps (CMJs).Methods:Thirty-five men and 35 women performed CMJs on a force platform during four testing sessions each separated by 1 wk. Kinematic variables included time in the air (TIA), take-off velocity (TOV), total vertical displacement of the center of mass (TJH). and countermovement depth, whereas kinetic variables included positive impulse, negative impulse, vertical stiffness, and rates of force development. Systematic bias was assessed by calculating the 90% confidence interval of the change in the mean between consecutive testing sessions and between the first and final testing session for each variable. Coefficients of variation (CV) and intraclass correlation coefficients (ICC) were also calculated.Results:Systematic bias was observed only for peak rate of force development during the concentric phase of the movement. For TIA, TOV, and TJH, CV values ranged from 1.7% to 6.6%, with ICC values ranging from 0.82 to 0.97. The other variables showed greater variation (CV range: 1.7% to 39.9%; ICC range: 0.04 to 0.99). Only slight gender differences were found in the reliability statistics, and the reliability of most of the variables was diminished as the time between the testing sessions was increased.Conclusion:Even though practitioners can expect good reliability for jump height measured from a force platform in men and women, other kinematic and kinetic variables often assessed during vertical jumps may not be reliable.

The purpose of this study was to determine the effect of stretching on peak jump height during a series of vertical jumps, specifically focusing on a) static stretching (SS), b) dynamic stretching (DS) and c) no stretching (NS) performed immediately before a series of countermovement vertical jumps (CMJ). Twelve female collegiate volleyball players (mean +/- SD; age 19.5 +/- 1.1 yr; height 1.71 +/- 0.06 m; mass 71.3 +/- 8.54 kg) volunteered for this study. Data collection lasted a total of 3 weeks, and each subject performed all 3 stretching protocols, 1 session per week, with 1 week between sessions. The order of the stretching protocols was randomized for each subject. During each testing session, all subjects performed a 5-minute light jog as a warm-up, followed by 8 minutes of 1 of the stretching protocols. One minute after the completion of each protocol, 5 maximal CMJ were performed on a force platform, with each jump separated by 1 minute of passive recovery. Jump heights were calculated by integrating the vertical force trace. There were no significant differences between the SS, DS, and NS conditions for any of the jumps (p > 0.05). Despite the lack of significant effects for the group, there were notable individual responses to each of the warm-up conditions. Practitioners should be aware of the individual responses of their athletes to different types of warm-up protocols before athletic performance and the possible impact of prescribing or eliminating certain exercises.

The integrin receptor alpha(v)beta(3) is overexpressed on the endothelial cells of growing tumors and on some tumor cells themselves. Radiolabeled alpha(v)beta(3) antagonists have demonstrated potential application as tumor imaging agents and as radiotherapeutic agents. This report describes the total synthesis of eight new HYNIC and DOTA conjugates of receptor alpha(v)beta(3) antagonists belonging to the quinolin-4-one class of peptidomimetics, and their radiolabeling with (99m)Tc (for HYNIC) and (111)In (for DOTA). Tethering of the radionuclide-chelator complexes was achieved at two different sites on the quinolin-4-one molecule. All such derivatives maintained high affinity for receptor alpha(v)beta(3) and high selectivity versus receptors alpha(IIb)beta(3), alpha(v)beta(5), alpha(5)beta(1). Biodistribution of the radiolabeled compounds was evaluated in the c-neu Oncomouse mammary adenocarcinoma model. DOTA conjugate (111)In-TA138 presented the best biodistribution profile. Tumor uptake at 2 h postinjection was 9.39% of injected dose/g of tissue (%ID/g). Activity levels in selected organs was as follows: blood, 0.54% ID/g; liver, 1.94% ID/g; kidney, 2.33% ID/g; lung, 2.74% ID/g; bone, 1.56% ID/g. A complete biodistribution analysis of (111)In-TA138 and the other radiolabeled compounds of this study are presented and discussed. A scintigraphic imaging study with (111)In-TA138 showed a clear delineation of the tumors and rapid clearance of activity from nontarget tissues.