Jay Dawes

The Effect of Position on the Percentage of Body Mass Supported During Traditional and Modified Push-up Variants

Introduction: The use of oral fluid for monitoring drug consumption on roads has many advantages over conventional biological fluids; therefore, several immunoassays have been developed for this purpose. In this work, the ability of 3 commercial immunoassays to detect amphetamine-type stimulants (ATSs) in oral fluid was assessed. In addition, it was reviewed the main controlled ATSs available worldwide, as well as the oral fluid immunological screening tests that have been used for identifying ATSs in drivers. Materials and Methods: The analytical specificity of amphetamine direct enzyme-linked immunosorbent assay (ELISA), methamphetamine direct ELISA (Immunalysis Corporation), and Oral-View saliva multidrug of abuse test (Alfa Scientific Designs) was evaluated using ATS-spiked oral fluid. Legislation and published articles that report the use of immunological screening tests to detect ATS consumption in conductors were reviewed, including the kits technical information, project reports, police and drug databases. Results and Discussion: Even at high concentrations, the tested assays were not able to detect methylphenidate, fenproporex, or diethylpropion, controlled ATSs legally marketed in many countries. Conclusions: This evidences the need to develop new kits that enable one to control the misuse of prescription ATSs on roads through oral fluid immunoassays.The push-up is a popular upper-extremity weight-bearing exercise. However, limited information is available regarding its effectiveness. Much of the past research has focused on muscle activation levels, whereas very little has examined the forces encountered during push-up variants. The purpose of the present study was to examine the effect of position within the range of motion on the percentage of body mass (BM) supported by the upper extremities during the traditional and modified (knees-down) push-up. Twenty-eight highly strength-trained male subjects were positioned with their hands on a force platform in 4 static positions, consisting of the up and down position in both the traditional and modified push-up exercise. The performance measures included the average vertical ground reaction force (GRF), expressed as a percentage of BM, supported in each of the 4 static positions and the percentage of change between the up and down positions in each push-up exercise. In both the traditional and modified push-ups, subjects supported less weight in the up vs. the down position. The percentage change in % BM from the up to the down position was greater in the modified push-up variant. The pattern of resistances to the push-up exercises observed in this study may be a result of differing moment arms between the support surface contact point (knees or feet) and the hands. These results may be useful in prescribing programs for strengthening and/or rehabilitation for both the prime movers and stabilizers of the upper extremity. Further, range of motion may need to be altered to accommodate strength differences in beginners and clients rehabilitating from injury.

A Cross-sectional and Retrospective Cohort Analysis of the Effects of Age on Flexibility, Strength Endurance, Lower-body Power, and Aerobic Fitness in Law Enforcement Officers

Abstract Lockie, RG, Dawes, JJ, Kornhauser, CL, and Holmes, RJ. Cross-sectional and retrospective cohort analysis of the effects of age on flexibility, strength endurance, lower-body power, and aerobic fitness in law enforcement officers. J Strength Cond Res 33(2): 451–458, 2019—There can be a great age range in cohorts of law enforcement officers. As the tasks required of officers generally do not change with advancing age, it is important to understand how physical performance in tests that assess job-specific characteristics may be altered. Retrospective analysis of performance test data of 383 officers (362 men and 21 women) was conducted. The tests included the following: sit-and-reach to determine hamstring and lower back flexibility; maximal push-up and sit-up repetitions in 60 seconds to measure muscle endurance; vertical jump (VJ) to assess lower-body power; and 2.4-km run to ascertain aerobic capacity. Data were stratified by age into 20–29, 30–39, 40–49, and 50–59 year groups, and analyzed by sex. A 1-way analysis of variance with the Bonferroni post hoc test was used to calculate the differences between the groups. Considering the male subjects, the 40–49 and 50–59 year groups performed poorer in the VJ, sit-up test, and 2.4-km run compared with the 20–29 year group (p ⩽ 0.001–0.045). For the female subjects, the 20–29 year group was superior to the 30–39 (p = 0.013) and 40–49 (p = 0.025) year groups in the push-up test. To ensure that an older officer can successfully complete occupation-specific tasks, lower-body power, abdominal strength, and aerobic training should be completed. Female officers should also attempt to maintain relative upper-body strength. Practitioners must attempt to design training programs that fit within the context of the occupational demands, and potentially using a nontraditional training design as law enforcement officers may not have the time to follow a traditional periodization model.

Resistance Characteristics of the TRX™ Suspension Training System at Different Angles and Distances from the Hanging Point

Resistance Characteristics of the TRX™ Suspension Training System at Different Angles and Distances from the Hanging Point The purpose of this research was to descriptively evaluate the percentages of body mass resistance experienced by users of the TRX™ suspension training system (STS) at different angles and distances from the hanging point. This information will be used to develop prediction equations and better prescribe resistance using this mode of exercise. Forty female and male college students were used as subjects. The TRX™ STS was connected to a dynamometer, suspended from a power rack. From the standing position, subjects leaned back and held the TRX™ handles at arm’s length at 30°, 45o, 60o, and 75o with their feet directly under the hanging point. Dynamometer readings were taken at each degree increment. Each angular measurement was repeated at 30.5 cm increments moving away from the hanging point. Prediction equations were calculated for each angle based on measurements taken at the hanging point. As the angle from standing increased, the amount of resistance encountered increased. On average, subjects experienced 37.44 ± 1.45% of their body mass at 30o, 52.88 ± 0.59% at 45o, 68.08 ± 1.95% at 60o, and 79.38 ± 2.14% at 75o from vertical. The effect of 30.5 cm increments moving away from the hanging point on resistance was somewhat variable. In conclusion, a decreased angle resulted in an increased body mass resistance during use. Increment changes produced progressive, linear variations in resistance. Prediction equations can allow more accurate predictions of resistance at the angles measured in this investigation..

The Effects of a Pre-Workout Energy Drink on Measures of Physical Performance

The purpose of this study was to investigate the effects of a pre-workout commercial energy drink on parameters of exercise performance, including anaerobic power, muscular endurance, speed, and reaction time. This study used a randomized, double blind, placebo controlled, parallel design. Participants visited the laboratory on two different occasions. On the first visit, participants were assessed for anaerobic power (via a vertical jump test), muscular endurance, reaction time, reactive sprint test, and aerobic power (via a 1.5 mile run). On the second visit, participants were randomly assigned to ingest four ounces of the energy drink beverage or a similar-tasting placebo beverage 30-minutes prior to engaging in these same physical performance tests. The energy drink treatment had no effect on anaerobic power (vertical jump), reaction time, reactive sprint test, or aerobic power. For the push-up to fatigue test, a significant difference (p = 0.014) was observed with the energy drink treatment enhancing performance by 12% as compared to the placebo treatment (improvement of ~ 4%). For the sit-up to fatigue test, a non-significant difference (p = 0.075) was observed with the energy drink treatment resulting in an enhancement of performance by ~13% as compared to no improvement for the placebo treatment. In light of these findings, individuals whose upper-body muscular endurance performance is part of their physical fitness assessment program may benefit from pre-workout energy drink consumption. In contrast, individuals needing to demonstrate anaerobic/aerobic power, or reactive abilities should not expect an improvement in performance from pre-workout energy drink consumption.

Self-reported Physical Tasks and Exercise Training in Special Weapons and Tactics (swat) Teams

Abstract Davis, MR, Easter, RL, Carlock, JM, Weiss, LW, Longo, EA, Smith, LM, Dawes, JJ, and Schilling, BK. Self-reported physical tasks and exercise training in Special Weapons and Tactics (SWAT) teams. J Strength Cond Res 30(11): 3242–3248, 2016—Little research has been done examining the most physically demanding tasks a SWAT officer may perform in the line of duty. Our objective was to analyze the rankings of tasks by SWAT officers based on frequency, difficulty, and importance and assess if training is addressing traits needed for successful task completion. A survey was designed using Qualtrics (Qualtrics Labs Inc). The survey had a demographics section, performance section, and training section. Officers were contacted by phone or e-mail and asked about interest in participating. Officers who agreed were sent the survey. Our results found a strong correlation between frequency of task and importance (r = 0.69, p = 0.001), and a moderate correlation was found between task difficulty and importance (r = 0.37, p = 0.005). Task rankings were averaged across the 3 domains to assess “overall” importance, and the top 3 tasks were assessed for necessary traits for successful performance. Power and strength were determined to be the most important traits for successful performance. Officers ranked the top 2 focuses of their training program in the training section as stamina/muscular endurance and cardiovascular/respiratory endurance. Training programs for SWAT officers should be developed to improve performance of the tasks with the highest “overall” importance. Therefore, a training program should emphasize strength and power improvements while not neglecting other measures of fitness.

Effect of a pre-exercise energy drink (Redline®) on muscular endurance of the trunk

Background Muscular endurance of the trunk is associated with successful performance in athletics, as well as activities of daily living. Furthermore, muscular endurance of the trunk may also play a critical role in injury prevention by allowing individuals to better withstand the effects of repetitive stressors. Pre-exercise, high energy supplements are frequently consumed as a method of improving exercise performance during an acute bout of exercise. Thus, the use of such supplements prior to an exercise session may allow the lifter to perform a greater total volume of work during training sessions. The purpose of this study was to investigate the effect of a high energy liquid supplement on a muscular endurance exerciseof the trunk. Methods Forty-one (n=41) healthy males (21.73 ± 1.74 yrs; 176.48 ± 7.54 cm; 81.16 ± 10.94 kg) volunteered to participate in this study. All test subjects completed a health history and caffeine usage questionnaires, as well as a consent form prior to participation. Subjects completed a pre and post sit-up to fatigue test within a week of one another. During the post-test session subjects were either given four ounces of an energy supplement (Redline by VPX) or a placebo, 30 minutes prior to testing. Administration of the supplement was double blind. Twenty-three (n=23) subjects received the supplement, while eighteen (n=18) subjects received the placebo. A 2 x 2 factorial ANOVA was used to determine between group differences for the muscular endurance assessments,at an alpha level of 0.10. Results

Effect of a pre-exercise energy drink (Redline®) on upper-body muscular endurance performance

Background Energy supplements are frequently consumed by athletes and recreational fitness enthusiasts as a method of improving exercise performance. Recent research indicates that these types of supplements influence exercise performance by increasing the number of repetitions that can be performed during an acute bout of exercise, thus increasing the total volume of work that can be performed during training sessions (Hoffman et al., 2008). Therefore, when aiming to improve muscular endurance performance the use of such a supplement may enhance one’s ability to withstand fatigue. The purpose of this study was to investigate the effect of a high energy liquid supplement on upper-body muscular endurance performance. Methods Forty-one healthy males (21.73 ± 1.74 yrs; 176.48 ± 7.54 cm; 81.16 ± 10.94 kg) volunteered to participate in this study. All test subjects completed a health history and caffeine usage questionnaire, as well as an informed consent form, prior to participating. Subjects completed a pre and post push-up to fatigue test within a week of one another. During the post-test session subjects were either given four ounces of an energy supplement (Redline by VPX) or a placebo, 30 minutes prior to the push-up to fatigue test. Administration of the supplement was double blind. Twenty-three (n=23) subjects received the supplement, while eighteen (n=18) subjects received the placebo. A 2 x 2 factorial ANOVA was used to determine between group differences for the muscular endurance assessment, at an alpha level of 0.05. Results Data analysis revealed a significant interaction between the treatment effect and the trials, F (1, 40) = 4.13, p = 0.024. Moreover, no significant difference was found between the pretest treatment group and the pretest placebo group, F (1, 40) = 3.07, p = 0.09, indicating that all subjects began the study with similar upper-body muscular endurance. Further examination of posttest main effects revealed a significant difference between the treatment group and the placebo group, F (1, 40) = 6.99, p = 0.01. The pretest push-up scores were similar for the treatment (52.91 ± 18.93) and the placebo group (44.22 ± 10.28). However, the treatment group showed substantially greater push-up scores for the posttest (59.34 ± 19.58) than the placebo group (45.66 ± 11.16). This represented a 12.15% increase in the treatment group’s posttest scores and a 3.25% increase in the placebo group’s posttest scores. Conclusions The results of this study indicate that the pre-exercise, liquid energy drink energy supplement investigated in this research had a significant effect on upper-body muscular endurance as measured by the push-up to fatigue test.

Guidelines for Fibromyalgia

FIBROMYALGIA (FM) IS A common yet poorly understood disorder characterized by widespread musculoskeletal pain and debilitating fatigue. It is estimated that as many as 10 million Americans have FM, which makes it the second most diagnosed disorder in rheumatology clinics after osteoarthritis (1). The symptoms of FM are as diverse as the individuals who suffer from it. The most common symptoms, in addition to pain and fatigue, include anxiety, depression, nonrestorative sleep, heightened pain perception, gastrointestinal distress, headaches, sensitivity to light, joint swelling, mood swings, and cognitive impairment (aka Fibro Fog). Although there are many theories, the cause of FM remains a mystery, making diagnosis extremely difficult. No objective findings or diagnostic tests have confirmed an abnormality; thus, diagnosis is largely based on self-reported symptoms. For these reasons, FM is an area of considerable debate. Many people in the medical community question whether FM even exists, and some consider it a psychological manifestation rather than an actual physical disorder. But in 1990, the American College of Rheumatology set specific guidelines for the diagnosis of FM. It was concluded that FM could be diagnosed by a history of widespread musculoskeketal pain occurring for longer than 3 months in combination with bilateral tender points in 11 out of 18 specified anatomical sites (3). Although a cure for FM is not currently available, management strategies that are in use include medication, counseling, massage, proper nutrition, and exercise. Most experts agree that regular, low-to-moderate intensity exercise is the most effective of these options (1–4). Unfortunately, exercise can also aggravate symptoms and initially may worsen a client’s condition. For this reason, many people with FM avoid exercise, and as a result become deconditioned. The more deconditioned people with FM become, the less functional ability they retain and thereby their ability to perform basic activities such as driving a car, washing dishes, or working is decreased. For individuals with FM, exercise results in improved sleep patterns, improved pain management, increased energy levels, stress management, increased self-esteem through the development of an internal locus of control, and acts as a natural antidepressant (2).