No abstract

No abstract

No abstract

No abstract

No abstract

Research suggests that caffeine can enhance measures of muscular strength in the upper and lower extremities, although the literature is somewhat equivocal. Little is known on whether or not caffeine will improve maximal inspiratory pressure (MIP), a surrogate measure of inspiratory muscle strength. The purpose of the study was to determine the effects of a moderate dose of caffeine on inspiratory muscle function. Fifteen (8 male, 7 female) healthy adults (mean ± SD: age = 24.3 ± 6.4 years; height = 1.75 ± 0.11 m; body mass = 78.8 ± 16.5 kg) volunteered to participate in the study which used a double-blind, placebo-controlled, cross-over design. During the initial visit, baseline data was collected and participants were familiarized with inspiratory muscle measurements. For the second and third visits, participants ingested either a 5 mg kg −1 dose of caffeine (CAF) or placebo capsule (PL). After one hour, they completed at least 12 maximal inspiratory manoeuvres with 1 min rest between each attempt. MIP, maximal inspiratory peak pressure (PP), and maximal rate of pressure development (MRPD) were recorded. The CAF trial resulted in significantly higher MIP (154.7 ± 35.8 vs. 146.6 ± 37.6 cmH 2 O; p = 0.02) and PP (165.8 ± 36.8 vs. 158.3 cmH 2 O; p = 0.01) compared to the PL condition. No significant difference was observed in MRPD (p = 0.18). MIP and PP improved after ingestion of caffeine compared to the placebo condition. The findings from the study further establish caffeine's potential ergogenic benefit on measures of muscular strength.

Background: The teaching strategies of modeling and the use of cue words are employed by both experienced and inexperienced teachers. While these strategies have received some attention in the literature, the effectiveness of these strategies in terms of the resultant change in the quality or kinematics of the motor skill performance has been limited. Purpose: To investigate the influence of cue words, when given independently and in conjunction with a modeled performance, on the qualitative or process characteristics (kinematics) of a motor skill. Participants and setting: Thirty kindergarten children participated in this study from a rural school in southern USA. Research design: A repeated measures design was employed to expose the participants to several teaching methodologies. Random assignment to order of methodology presentation was utilized. Data collection: Participants were pre-tested on the horizontal jump, initiated by the command, 'jump as far as you can'. The participants were then randomly assigned to either the cue word only condition or the model condition, and asked to jump again. Finally, the participants were exposed to both the cue words and the model together and asked to jump again. Data analysis: Two (shoulder angle and knee angle) Analyses of Variance (ANOVA) were used to determine differences between teaching strategy groups and conditions. Each assessment set produced data for a 2 × 3 (strategy × condition) mixed design with repeated measures on the last factor. Findings: The shoulder angle noted a significant difference between the pre and the cue word only conditions (p , 0.01) and between the pre and the model and cue condition, for the cue-only participants (p , 0.01). However, statistical analysis of the maximum relative knee flexion angle prior to the participant's feet leaving the ground yielded no significant difference (F(2,15) = 2.887, p = 0.087, h 2 = 0.278) across the three trial conditions. Conclusions: Results indicated that cue words used independently or in conjunction with a visual model influenced the kinematics of the skill.

No abstract