Lactate accumulation following isometric exercise training and its relationship with reduced resting blood pressure

The purpose of this study was (a) to assess lactate accumulation during isometric exercise, and to quantify the shifts in accumulation following isometric training; and (b) to relate any training-induced changes in lactate accumulation to reductions in resting blood pressure. Eleven male participants undertook isometric training for a 4-week period using bilateral-leg exercise. Training caused reductions in systolic, diastolic, and mean arterial resting blood pressure (of -4.9 ± 6.3 mmHg, P = 0.01; -2.6 ± 3.0 mmHg, P = 0.01; and -2.6 ± 2.3 mmHg, P = 0.001 respectively; mean ± s). These were accompanied by changes in muscle activity, taken as electromyographic activity to reach a given lactate concentration (from 114 ± 22 to 131 ± 27 mV and from 136 ± 25 to 155 ± 34 mV for 3 and 4 mmol · L(-1) respectively. Training intensity expressed relative to peak lactate was correlated with reduced resting systolic and mean arterial blood pressure. Training caused significant shifts in lactate accumulation, and reductions in resting blood pressure are strongly related to training intensity, when expressed relative to pre-training peak lactate. This suggests that higher levels of local muscle anaerobiosis may promote the training-induced reductions in resting blood pressure.     

The Contextual Importance of Diversity: The Impact of Relational Demography and Team Diversity on Individual Performance and Satisfaction

ABSTRACT : Organizations are seeing an increase in the level and types of diversity among their employees. It is important that managers understand the myriad of ways that diversity influences employees. This study investigates the effect of being different on an individual's performance and satisfaction levels. Being different on visible characteristics (i.e., sex, age, race) predicted negative outcomes. Being different on informational characteristics (educational background, years of work experience) had both positive and negative effects on objective performance but no effect on satisfaction or perceived performance. The level of team diversity (the degree to which a team is heterogeneous and homogeneous) influenced the outcomes above and beyond that of being different. The results of this study have real consequences for the way diversity is managed in organizations.