22 research outputs found
The acute effects of multi-ingredient pre-workout ingestion on strength performance, lower body power, and anaerobic capacity
EFFECTIVENESS OF A POSTACTIVATION PROTOCOL FOR IMPROVING PERFORMANCE IN THE ARMY COMBAT FITNESS TEST
Christopher Bonilla1, Robert L. Herron1, Greg A. Ryan2, Jason C. Casey3, Brandon D. Spradley1. 1United States Sports Academy, Daphne, AL. 2Piedmont University, Demorest, GA. 3University of North Georgia, Gainesville, GA.
The Army Combat Fitness Test (ACFT) aims to accurately reflect Soldier combat performance capability and includes a 3-rep-max deadlift (MDL), standing power throw (SPT), hand-release pushup (HRP), sprint-drag-carry (SDC), leg tuck (LTK), and two-mile run (2MR). The benefits of the current warmup protocol, known as the âPreparation Drillâ, performed prior to the first event of the ACFT, is limited by subsequent idle periods in between events. This study was designed to evaluate the effectiveness of implementing task-specific, post activation performance enhancement (PAPE) strategies, performed immediately prior to the event for which PAPE exercises are designed. The PAPE strategies were as follows: MDL = 1 rep at 10% higher than target 3RM, SPT = 5 consecutive vertical jumps, HRP = 5 plyometric pushups, SDC = 5 consecutive broad jumps, LTK = 5 medicine ball slams, and 2MR = 4 x 20 m sprints. METHODS: A total of 19 ROTC members completed two ACFT tests, separated by 72 hours. Approximately half (n = 10) completed the traditional âPreparation Drillâ as their warmup prior to the first session and added PAPE warmup strategies as part of their second session. The remainder of the group (n = 9) completed the treatments in the opposite order to facilitate a repeated-measures, crossover design. The participantsâ composite ACFT score (passing score = 360, max = 600 pts) was used to test for mean difference in a two-way (Time x Treatment), repeated measures ANOVA. RESULTS: The results of the two-way repeated measures ANOVA revealed that there was no interaction effect (Time x Treatment) (F(1,8) = 0.075, p = 0.79, ηp2 = 0.009) nor main effect of Treatment (F(1,8) = 0.084, p = 0.78, ηp2 = 0.010). However, there was a main effect of Time (F(1,8) = 58.87, p \u3c 0.001, ηp2 = 0.88) (mean ACFT score ± SD: Session 1 = 527 ± 43, Session 2 = 537 ± 39). CONCLUSION: The results of this study did not support the use of additional PAPE strategies to improve ACFT performance. Of note, all passed by a large margin (range 428 - 600). Additionally, there was a practice effect when the test was completed twice, separated by 72 hours - with 17/19 participants matching or exceeding their first score. Therefore, further investigation is warranted with particular attention to minimizing the impact of familiarization and targeting soldiers whose scores are closer to the passing threshold for some - or all - events
RELATIONSHIP BETWEEN VISUAL ANALOG SCALES AND COMMONLY USED SCALES OF PERCEIVED READINESS AND EXERTION
Robert L. Herron1, Christopher P. Bonilla1, Greg A. Ryan2, Jason C. Casey3, Brandon D. Spradley1. 1United States Sports Academy, Daphne, AL. 2Piedmont University, Demorest, GA. 3University of North Georgia, Gainesville, GA.
BACKGROUND: Subjective measures of perceived readiness and exertion are widely used in research and practical settings. However, these data are ordinal in nature and present unique challenges during analysis and interpretation. The purpose of this study was to investigate the correlation of two visual analog scales (VAS) to their counterparts for readiness and exertion metrics. METHODS: A sample of 20 ROTC participants (female n = 1, aged 18-28 y) participated this study. Participants were asked to provide subject measures of readiness (before) and exertion (after) completing the Army Combat Fitness Test (ACFT) during two sessions. Upon arrival, participants were asked to report their perceived readiness on a commonly-used perceived readiness scale (PRS: 0-10) and on a modified visual analog scale of perceived readiness (100-mm line anchored with âUnable to Performâ and âReady for Peak Performanceâ). Then, all participants completed the current Army Combat Fitness Test (ACFT) and reported post session ratings of perceived exertion on the Omni scale (Omni RPE: 0-10) and a modified visual analog scale of perceived exertion (100-mm line anchored with âRest/No Exertionâ and âMaximal Exertionâ). VAS scoring required the participant to mark on the 100-mm line where they fell on the spectrum and their score was later measured to the nearest millimeter the line passed. The protocol was repeated 72 h later. Data from both sessions were pooled for analysis for each comparison. Spearmanâs Rho correlations were used to explore the relationships between the visual analog scales and their traditional, ordinal counterparts. RESULTS: The results of the Spearmanâs Rho correlations showed moderately-strong correlations between the measures of readiness (rs(37) = 0.65, p \u3c 0.001) and exertion (rs(35) = 0.77, p \u3c 0.001). Of note, one participant did not complete session two and participant errors on the data collection sheet for Omni RPE called for the removal of two exertion-related data points. CONCLUSION: These data show that both visual analog scales have moderately-strong relationships with traditionally-used subjective metrics for readiness and exertion - establishing a level of criterion validity. Therefore, visual analog scales show promise as tool with which researchers and practitioners can assess subjective responses and be confident the data are continuous, limiting bias related to recall with serial measures
Stress is dominant in patients with depression and chronic low back pain. A qualitative study of psychotherapeutic interventions for patients with non-specific low back pain of 3â12 monthsâ duration
<p><b>Abstract</b></p> <p>Background</p> <p>There is continuing uncertainty in back pain research as to which treatment is best suited to patients with non-specific chronic low back pain (CLBP). In this study, Gestalt therapy and the shock trauma method Somatic ExperiencingÂź (SE) were used as interventions in parallel with the usual cross-disciplinary approach. The aim was to investigate how these treatments influence a patientâs capacity to cope with CLBP when it is coupled with depression.</p> <p>Methods</p> <p>In this qualitative explorative study, a phenomenologicalâhermeneutic framework was adopted. Patients were recruited on the basis of following criteria: A moderate depression score of 23â30 according to the Beck Depression Inventory Scale and a pain score of 7â10 (Box scale from 0â10) and attendance at five- six psychotherapeutic sessions. Six patients participated in the study. The data was comprised of written field notes from each session, which were subsequently analysed and interpreted at three levels: naive reading, structural analysis and critical interpretation and discussion.</p> <p>Results</p> <p>Three areas of focus emerged: the significance of previous experiences, restrictions in everyday life and restoration of inner resources during the therapy period. The study revealed a diversity of psychological stressors that related to loss and sorrow, being let down, violations, traumatic events and reduced functioning, which led to displays of distress, powerlessness, reduced self-worth, anxiety and discomfort.</p> <p>Overall, the sum of the stressors together with pain and depression were shown to trigger stress symptoms. Stress was down-played in the psychotherapeutic treatment and inner resources were re-established, which manifested as increased relaxation, presence, self-worth, sense of responsibility and happiness. This, in turn, assisted the patients to better manage their CLBP.</p> <p>Conclusions</p> <p>CLBP is a stress factor in itself but when coupled with depression, they can be regarded as two symptom complexes that mutually affect each other in negative ways. When pain, stress and depression become overwhelming and there are few internal resources available, <it>stress</it> seems to become prominent. In this study, Gestalt therapy and the SE-method may have helped to lower the six patientsâ level of stress and restore their own internal resources, thereby increasing their capacity to cope with their CLBP.</p
Sex estimation: a comparison of techniques based on binary logistic, probit and cumulative probit regression, linear and quadratic discriminant analysis, neural networks, and naĂŻve Bayes classification using ordinal variables
The profitable adventure of threatened middle-class families: an ethnographic study on homeschooling in South Korea
Effects of two pre-workout supplements on concentric and eccentric force production during lower body resistance exercise in males and females: a counterbalanced, double-blind, placebo-controlled trial
Abstract Background Pre-workout supplements purportedly enhance feelings of energy, reduce fatigue and improve exercise performance. The purpose of this study was to examine the performance effects of caffeinated and non-caffeinated multi-ingredient pre-workout supplements. Methods In a counterbalanced, double-blind, placebo-controlled design, eccentric and concentric force production during lower body resistance exercise on a mechanized squat device were assessed after supplement ingestion. Repetitions-in-reserve/RPE and subjective feelings of energy, focus and fatigue were also examined. Twenty-one resistance-trained adults (12Â F, 9Â M) completed three conditions in random order: caffeinated supplement, non-caffeinated supplement and placebo. Subjects were not informed of the presence of a placebo condition. Thirty minutes after supplement ingestion, a 3-repetition maximum test and 5 sets of 6 repetitions were completed using the squat device. Each repetition involved 4-s eccentric and concentric phases, and the force signal throughout each repetition was sampled from a load cell contained within the squat device. The scaled and filtered force signals were analyzed using customized software. Repeated measures analysis of variance and appropriate follow-up analyses were utilized to compare dependent variables, and relevant effect sizes (d) were calculated. Results Supplement or placebo ingestion led to similar subjective responses (pâ>â0.05). Energy (+8 to 44%; dâ=â0.3 to 0.8) and focus (+8 to 25%; dâ=â0.3 to 0.5) were acutely increased by supplement or placebo ingestion and decreased as the exercise session progressed. Fatigue was acutely decreased by supplement or placebo ingestion (â7 to 38%; dâ=ââ0.1 to â0.6) and increased as the exercise session progressed. Eccentric and concentric forces were unimproved by supplementation during the exercise sets for both sexes. In the non-caffeinated supplement condition only, maximal eccentric force production was lower during sets 3 to 5, as compared to set 1 (pâ<â0.05). Effect size data indicated that both the caffeinated and non-caffeinated supplements may contribute to small increases in concentric force production in males (+5 to 20%, dâ=â0.2 to 0.4 relative to placebo), but not females. Conclusions As compared to placebo, caffeinated and non-caffeinated multi-ingredient pre-workout supplements failed to improve concentric and eccentric force production. In males, effect size data indicate a possible small benefit of supplementation on concentric force production, although this was not statistically significant. When resistance-trained subjects were unaware of the presence of a placebo, resistance exercise performance was similar regardless of whether a placebo or multi-ingredient supplement was ingested