Daniel G. Drury

Effect of load position on physiological and perceptual responses during load carriage with an internal frame backpack

The purpose of this study was to determine the effect of load position in an internal frame backpack on physiological and perceptual variables. Ten female participants walked on a level treadmill for 10 min carrying 25% of their body weight in a high, central, or low position. The variables measured included oxygen consumption (VO2), heart rate (HR), respiratory exchange ratio (R), respiratory rate (RR), minute ventilation (VE), and rating of perceived exertion (RPE). VO2, VE, and RPE were significantly lower in the high position (18.6 ± 2.3 ml/kg/min, 31.7 ± 5.0 l/min, 2.8 ± 0.8, respectively) compared to the low position (22.2 ± 3.0 ml/kg/min, 38.6 ± 7.5 l/min, 3.7 ± 1.0, respectively). HR, R, and RR did not change significantly as the load was moved from the high (129.8 ± 16.8, 0.89 ± 0.06, 30.3 ± 4.2, respectively) to the low position (136.0 ± 25.3, 0.92 ± 0.04, 33.8 ± 5.2, respectively). The results of this study suggest that load placement is an important factor in the physiological and perceptual responses to load carriage, and that packing heavy items high in the backpack may be the most energy efficient method of carrying a load on the back.

The effects of isokinetic contraction velocity on concentric and eccentric strength of the biceps brachii.

The purpose of this investigation was to determine the influence of contraction velocity on the eccentric (ECC) and concentric (CON) torque production of the biceps brachii. After performing warm-up procedures, each male subject (n = 11) completed 3 sets of 5 maximal bilateral CON and ECC isokinetic contractions of the biceps at speeds of 90, 180, and 3008·s−1 on a Biodex System 3 dynamometer. The men received a 3-minute rest between sets and the order of exercises was randomized. Peak torque (Nm) values were obtained for CON and ECC contractions at each speed. Peak torque scores (ECC vs. CON) were compared using a t-test at each speed. A repeated measures analysis of variance was used to determine differences between speeds. ECC peak torque scores were greater than CON peak torque scores at each given speed: 908·s−1, p = 0.0001; 1808·s−1, p = 0.0001; and 3008·s−1, p = 0.0001. No differences were found between the ECC peak torque scores (p = 0.62) at any of the speeds. Differences were found among the CON scores (p = 0.004). Post hoc analysis revealed differences between 908·s−1 (114.61 ± 23) and 3008·s−1 (94.17 ± 18). These data suggest that ECC contractions of the biceps brachii were somewhat resistant to a force decrement as the result of an increase in velocity, whereas CON muscular actions of the biceps brachii were unable to maintain force as velocity increased.

Development of a Rowing-Specific Oo2max Field Test

Huntsman, HD, DiPietro, L, Drury, DG, and Miller, TA. Development of a rowing specific &OV0312;o2max field test. J Strength Cond Res 25(6): 1774-1779, 2011—The purpose of this study was to develop an aerobic capacity test for rowers using minimal equipment that could be used in the field. Thirty rowers (15 men and 15 women) between the ages of 18 and 26 years were recruited on a volunteer basis from the District of Columbia metro area. The testing protocol consisted of a maximum of 7 2-minute stages on a rowing ergometer, separated by 30-second breaks where lactic acid concentrations were analyzed. Starting intensity for men was 200 W, although women started at 150 W, and each stage increased by 50 W. Expired gasses were collected during the test, and athletes were asked to row until maximal volition so that the directly measured &OV0312;o2max could be compared to predicted values. Peak heart rates from each completed stage were plotted, and regression equations were calculated to predict &OV0312;o2max. Separate regression equations were calculated for men and women. The predicted &OV0312;o2max values were approximately 23 and 25% lower than what was actually achieved for men and women, respectively. Heart rate was a stronger correlate of &OV0312;o2max in men compared with in women. Among men, we observed a moderate and statistically significant correlation (r = 0.55; p = 0.05), whereas among women, no such agreement was observed (r = −0.05; p > 0.85). The principle finding of this study was that the test was adequate in predicting &OV0312;o2max in men but was inadequate in its prediction in women. With slight modifications to the testing protocol, stronger correlations and a more accurate prediction of &OV0312;o2max is expected in men.

Current Exercise Behaviors of Breast Cancer Patients Diagnosed with Chemotherapy-Induced Peripheral Neuropathy

Introduction: Chemotherapy-induced peripheral neuropathy (CIPN) is a common, dose-limiting effect of cancer therapy. The neuropathic pain associated with CIPN often has negative implications on an individuals quality of life (QOL) and has long been recognized as one of the more difficult types of pain to treat. Treatment of neuropathic pain due to CIPN often requires a multidisciplinary approach, with much attention focused on the use of pharmacological therapies. However, in most instances, these agents have been shown to have additional negative side effects for cancer patients. Thus, other interventions that address the symptoms of CIPN should be considered. One such possible intervention is exercise rehabilitation, which has previously been reported effective in attenuating numerous cancer treatment-related toxicities and enhancing the QOL of patients. However, to our knowledge, there have been no published clinical trials examining the role of exercise in preserving neurological function following chemotherapy. As such, the purpose of this investigation was to examine the current exercise habits of breast cancer patients who are diagnosed with CIPN and the impact on pain and QOL. Methods: 300 women listed in the Breast Cancer Registry of Greater Cincinnati database were recruited by mail and asked to complete three questionnaires (McGill QOL, Leeds Assessment of Neuropathic Symptoms and Signs, and Current Exercise Behaviors). Data was analyzed at the 0.05 level of significance using a students t-test and a Pearsons product moment correlation. Results: 134 completed surveys were returned and analyzed (44.6% response rate). Overall, QOL and exercise behaviors were moderately correlated (r = 0.56). Patients reported exercising an average of 2.3 d/wk and an overall QOL of 4.7. Of the patients completing the recommended amount of physical activity (EX, n = 21), QOL was 6.3, which was significantly higher than patients who did not meet these recommendations (SED, n = 113, p<0.001). Likewise, only 15% of EX patients reported experiencing pain compared to 72% of SED patients (p<0.001). Conclusions: Based on these data, it seems likely that an exercise intervention would be successful in attenuating symptoms of CIPN and improving the overall QOL of breast cancer patients.

An investigation of the tri-bar gripping system on isometric muscular endurance.

Recently, a new product called the Tri-Bar has been introduced as an alternative to the standard round weightlifting bar. The Tri-Bar has the same weight, length, and circumference as a standard weightlifting bar and differs only in that the shape of the bar is formed like a triangle with rounded edges. Theoretically, the shape of the bar will enhance gripping comfort and increase muscular endurance. We studied 32 moderately trained males who were free from upper-body injury or limitation. Each participant completed 4 visits to the lab as part of 2 separate investigations. The first investigation was a comparison of straight-arm hang times while grasping a standard Olympic bar or a Tri-Bar attached to the top of a power rack. The second investigation involved grasping a standard revolving cable handle or a Tri-Bar revolving handle attached to a weight equal to half the subjects body weight. In both investigations, time was used as a measure of isometric muscular endurance. Differences were determined using a dependent t-test, and a level of significance was set at p < 0.05. Mean hang times were significantly longer when the men hung from the Tri-Bar (107.6 seconds) versus the standard bar (95.4 seconds) (p = 0.015). Conversely, in the investigation using the revolving handles, the round bar produced longer grasping times (71.5 seconds) than the Tri-Bar (62.6 seconds) (p = 0.000). The results of this investigation indicate that a fixed and stable Tri-Bar may help to increase hang time, but a Tri-Bar free to rotate within the grasp may decrease grasping time in comparison to a standard round handle. With regard to exercises that require isometric grasping, the Tri-Bar may be an effective alternative to the standard bar for increasing isometric grasping endurance.

Ponderal Somatograms Assess Changes in Anthropometric Measurements Over an Academic Year in Division III Collegiate Football Players

Ponderal somatograms evaluate body size and shape by converting muscular (shoulders, chest, biceps, forearm, thigh, calf) and nonmuscular (abdomen, hips, knee, ankle, wrist) girths into ponderal equivalent (PE) values. Anthropometric measurements, including stature, body mass, girths, and percent body fat by densitometry were collected in 54 Division III football players in preseason camp (fall) and at the beginning (winter) and end (spring) of the team strength and conditioning program. PE values were calculated for each girth as PE, kg = (girth, cm / k)2 X stature, dm, where k = k constant from Behnkes reference man. PE values were compared to body mass to indicate overdevelopment (PE > body mass) and underdevelopment (PE > body mass) at specific girth sites. From fall to winter, body mass (+1.6 kg), percent fat (+1.3%), fat mass (+1.6 kg), non-muscular abdominal and hip girths (+2.1 cm, +1.5 cm), and PE values (+5.3 kg, +2.6 kg) increased significantly (p > 0.05). From winter to spring, percent fat (+1.5%), fat mass (+1.4 kg), nonmuscular abdominal girth (+1.0 cm), and PE value (+2.5 kg) decreased significantly (p > 0.05). Fat-free mass (+1.5 kg), muscular biceps girth (+0.4 cm), and PE value (+2.6 kg) increased significantly (p > 0.05) from winter to spring. Ponderal somatogram muscular components were generally overdeveloped, with the greatest overdevelopment at the biceps in fall (+14.7 kg), winter (+14.9 kg), and spring (+17.4 kg). Nonmuscular components generally were underdeveloped, except abdomen and hips that were overdeveloped. The abdomen remained the greatest nonmuscular overdevelopment in fall (+6.8 kg), winter (+10.5 kg), and spring (+7.9 kg). Ponderal somatograms provide a relatively simple, practical method to track specific changes in body size and shape over time.

Ponderal somatogram analysis of girth measurements by position in division III college football players.

Stuempfle, KJ, Drury, DG, Petrie, DF, and Katch, FI. Ponderal somatogram analysis of girth measurements by position in Division III college football players. J Strength Cond Res 23(3): 788-799, 2009-Ponderal somatograms assessed body composition in four groups of Division III collegiate football players: offensive line (OL), defensive line (DL), offensive backs (OB), and defensive backs (DB). Ponderal somatograms evaluate body size and shape by converting muscular (shoulders, chest, biceps, forearm, thigh, and calf) and nonmuscular (abdomen, hips, knee, ankle, and wrist) girths into ponderal equivalent (PE) values. Anthropometric measurements, including stature, body mass, girths, and percent body fat by densitometry were collected in 82 players (22 OL, 12 DL, 20 OB, and 28 DB) during preseason camp. PE values were calculated for each girth as PE, kilograms = (girth, cm ÷ k)2 × stature, decimeters, where k = k constant from Behnkes reference man. PE values were compared to body mass to indicate overdevelopment (PE > body mass) and underdevelopment (PE < body mass). OL was significantly heavier than DL (+15.6 kg), OB (+25.2 kg), and DB (+22.4 kg). OL percent fat was significantly greater than DL (+5.9%), OB (+9.0%), and DB (+9.3%). Similar differences occurred in girths and PE values by position. Muscular components were generally overdeveloped, with the greatest overdevelopment in the biceps (OL + 16.0 kg, DL + 19 kg, OB + 14.2 kg, and DB + 16.2 kg). Nonmuscular abdomen, hips, and knee were generally overdeveloped, with the greatest overdevelopment in the OL abdomen (+19.3 kg). Nonmuscular ankle and wrist were underdeveloped. Ponderal somatograms provide a relatively quick and simple method to translate girth measurements into ponderal equivalent values that seem to be position-specific among offensive and defensive linemen and backs. Somatograms provide an appraisal of body composition that helps coaches and athletes monitor the effectiveness of strength and conditioning programs.

The effect of caffeine ingestion on perception of muscle pain during a sustained submaximal isometric contraction of the quadriceps

Methods A total of 15 low caffeine consuming college aged women (20.5 ± 1.4 y, 66.0 ± 9.0 kg; mean ± SD) participated in this study. 2–7 d after a familiarization trial subjects ingested, in a double blind random crossover manner, either 5 mg/kg caffeine (Caf) or a placebo (P), 1 h prior to performing a 2 min isometric leg extension at 45% of peak torque using visual cues to maintain force production. Every 15 s subjects rated their level of pain using the Borg CR10 pain scale. Subjects returned to the lab 2–7 d later to repeat the testing with the other condition. Data were analyzed using a repeated measures ANOVA with a Tukeys HSD post hoc.

Exercise Intensity As A Determinant Of Exercise Induced Hypoalgesia: 2301

The purpose of this study was to examine pain perception during and following two separate 30-min bouts of exercise above and below the Lactate Threshold (LT). Pain Threshold (PT) and Pain Intensity (PI) were monitored during (15 and 30 min) and after exercise (15 and 30 min into recovery) using a Cold Pressor Test (CPT) and Visual Analog Scale (VAS) for pain of the non-dominant hand. Significant differences in PT scores were found both during and after exercise conditions. Post hoc analysis revealed significant differences in PT scores at 30 min of exercise (P=0.024, P=0.02) and 15 min of recovery (P=0.03, P=0.01) for exercise conditions above and below LT, respectively. No differences (P=0.05) in PT scores were found at any time point between exercise conditions. No differences were found in PI scores at any time point within each trial (P=0.05) as well as between exercise conditions (p=0.05). Based upon these data, the effects of moderate exercise on PT appear to be similar at exercise intensities just above and below LT. This may indicate that the requisite intensity needed to ellicit Exercise-Induced Hypoalgesia may be lower than previously reported. Because a hypoalgesic effect was not observed in either condition until 30 min of exercise had been completed, total exercise time may be an important factor in the augmentation of pain perception under these conditions.

Orthostatic-Induced Hypotension Attenuates Cold Pressor Pain Perception: 1792

In recent years, numerous studies have established a connection between blood pressure and nocioception. While this connection is well documented in the literature, its underlying physiological mechanisms have yet to be elucidated. Much attention has focused on the relationship between cardiovascular regulatory centers and nocioception, yet the intricacies of this relationship have not been fully explored. Therefore, the purpose of this investigation was to examine the role of the baroreflex system as a modulator of pain perception. Twenty normotensive males participated in two laboratory sessions. Time to cold pain threshold and pain tolerance was measured at rest during the first visit. On visit two, blood pressure was orthostatically manipulated via tilt table at postures 90o, 120o, and 180o. Orthostatic manipulation significantly lowered systolic blood pressure (SBP), pain threshold, and pain tolerance from seated baseline at 120o and 180o. The regression models for baroreceptor reflex sensitivity (BRS) assessed during seated baseline and at 120o and 180o revealed a significant negative beta weight for the effect of SBP. A significant negative beta weight for the effects of BRS, SBP, and their interaction was observed at 90o. In conclusion, orthostatic baroreceptor activation appears to exert an inhibitory effect on the brain that decreases pain sensitivity. This article is available at The Cupola: Scholarship at Gettysburg College: http://cupola.gettysburg.edu/healthfac/32 Orthostatic Hypotension and Pain Perception 21 Journal of Exercise Physiologyonline (JEPonline) Volume 13 Number 1 February 2010 Managing Editor Tommy Boone, PhD, MPH Editor-in-Chief Jon K. Linderman, PhD Review Board Todd Astorino, PhD Julien Baker, PhD Tommy Boone, PhD Eric Goulet, PhD Robert Gotshall, PhD Alexander Hutchison, PhD M. Knight-Maloney, PhD Len Kravitz, PhD James Laskin, PhD Derek Marks, PhD Cristine Mermier, PhD Chantal Vella, PhD Ben Zhou, PhD Official Research Journal of the American Society of Exercise Physiologists (ASEP) ISSN 1097-975 Systems Physiology Cardiopulmonary Orthostatic-induced Hypotension Attenuates Cold Pressor Pain Perception KAREN WONDERS and DANIEL DRURY Wright State University, Department of Health, Physical Education and Recreation, Dayton, OH 45435 USA, Gettysburg College, Department of Health Sciences, Gettysburg, PA, USA