Polymorphisms of the beta(2)-adrenergic receptor determine exercise capacity in patients with heart failure.

The beta(2)-adrenergic receptor (beta(2)AR) exists in multiple polymorphic forms with different characteristics. Their relevance to heart failure (HF) physiology is unknown. Cardiopulmonary exercise testing was performed on 232 compensated HF patients with a defined beta(2)AR genotype. Patients with the uncommon Ile164 polymorphism had a lower peak VO(2) (15.0+/-0.9 mL. kg(-1). min(-1)) than did patients with Thr164 (17.9+/-0.9 mL. kg(-1). min(-1), P<0.0001). The percentage achieved of predicted peak VO(2) was also lower in patients with Ile164 (62. 3+/-4.5% versus 71.5+/-5.1%, P=0.045). The relative risk of a patient having a VO(2)

Assessment of exercise-induced minor muscle lesions: the accuracy of Cyriax's diagnosis by selective tension paradigm.

The Cyriax selective tension assessment paradigm is commonly used by clinicians for the diagnosis of soft tissue lesions; however, studies have not demonstrated that it is a valid method. The purpose of this study was to examine the construct validity of the active motion, passive motion, resisted movement, and palpation components of the Cyriax selective tension diagnosis paradigm in subjects with an exercise-induced minor hamstring muscle lesion. Nine female subjects with a mean age of 23.6 years (SD = 4.7) and a mass of 57.3 kg (SD = 10.7) performed two sets of 20 maximal eccentric isokinetic knee flexor contractions designed to induce a minor muscle lesion of the hamstrings. Active range of motion, passive range of motion, knee extension end-feel pain relative to resistance sequence, knee flexor isometric strength, pain perception during knee flexor resisted movement testing, and palpation pain of the hamstrings were assessed at 0, 5, 2, 12, 24, 48, and 72 hours postexercise and compared with Cyriax's hypothesized selective tension paradigm results. Consistent with Cyriax's paradigm, passive range of motion remained unchanged, and perceived pain of the hamstrings increased with resistance testing at 12, 24, 48, and 72 hours postexercise when compared with baseline. In addition, palpation pain of the hamstrings was significantly elevated at 48 and 72 hours after exercise (p < 0.05). In contrast of Cyriax's paradigm, active range of motion was significantly reduced over time (p < 0.05), with the least amount of motion compared to baseline (85%) occurring at 48 hours postexercise. Further, resisted movement testing found significant knee flexor isometric strength reductions over time (p < 0.05), with the greatest reductions (33%) occurring at 48 hours postexercise. According to Cyriax, when a minor muscle lesion is tested, it should be strong and painful; however, none of the postexercise time frames exhibited results that were strong and painful. This study suggests that the validity of using Cyriax's selective tension testing for the diagnosis of exercise-induced minor muscle lesions is questionable.

Eosinophil recruitment is associated with IL-5, but not with RANTES, twenty-four hours after allergen challenge.

Several lines of evidence suggest that the chemokine RANTES may play a role in eosinophilia observed during allergic inflammation. To test this hypothesis, six patients with allergic asthma were studied. After performing bronchoalveolar lavage in a lung segment (baseline), segmental bronchoprovocation was performed with saline solution in another segment and with ragweed in a third segment. Bronchoalveolar lavage was performed 24 hours later in the saline-challenged (sham) and ragweed-challenged lung segments. The bronchoalveolar lavage fluids from the baseline, sham, and ragweed segments were analyzed for cell counts and for the levels of IL-5, RANTES, and eosinophil-derived neurotoxin. IL-5 levels were elevated in the ragweed (984 +/- 588 pg/ml) compared with sham segments (2.8 +/- 0.2 pg/ml, p = 0.02). Likewise, RANTES levels were elevated in the ragweed (12.93 +/- 3.4 pg/ml) compared with the sham segments (3.05 +/- 1.19 pg/ml, p = 0.006). The IL-5 levels correlated with both eosinophil numbers (r = 0.90, p < 0.02) and eosinophil-derived neurotoxin levels (r = 0.89, p < 0.02). In contrast, RANTES levels did not correlate with either eosinophil numbers or eosinophil-derived neurotoxin levels. These results indicate that although both IL-5 and RANTES are elevated 24 hours after allergen challenge, only IL-5 correlates with eosinophil recruitment and degranulation.

Effect of phonophoresis with dexamethasone on adrenal function.

One of the side effects of corticosteroid ingestion and inhalants is suppression of the adrenal glands. Phonophoresis of topically applied corticosteroids is commonly used to treat musculoskeletal inflammatory conditions. The purpose of this study was to determine whether phonophoresis with dexamethasone sodium phosphate affected adrenal function. The subjects included 28 male volunteers (mean = 25.3 years, SD = 6.4) who received phonophoresis to the left shoulder every other day for 2 weeks. Subjects were randomly assigned to one of four groups, including a control group (N = 8), an ultrasound group (N = 8), a .33% dexamethasone group (N = 7), and a ultrasound with .33% dexamethasone group (N = 5). Adrenal function was assessed by 24-hour urinary-free cortisol (microgram cortisol/g creatinine) collected two days prior to and following the phonophoresis treatments. A nonparametric analysis of variance using a split plot factorial design was calculated for ranked urinary-free cortisol scores and found no significant (p > 0.05) differences in urinary-free cortisol levels between the four groups and between the four collection days, and there were no significant (p > 0.05) interactions exhibited between group and collection day. This study suggests that phonophoresis with dexamethasone sodium phosphate, using common clinical parameters, does not cause dexamethasone sodium phosphate to become systemic in large enough quantities to impair adrenal function.

Effect of positive heel inclination on posture.

Millions of women wear high heels on a daily basis; however, few studies have analyzed the changes high heels (positive heel inclination) have on posture. The purpose of this study was to determine whether positive heel inclination changed the postural alignment of the head, spine, pelvis, and knees. Fifteen female college students ((mean age = 22.7, SD = 3.7 years) had sagittal plane angles measured for the cervical spine, thoracic spine, lumbar spine, sacral spine, and knee joints in addition to anterior/posterior displacements of the head and pelvis. All variables were assessed by a Metrecom Skeletal Analysis System, a three-dimensional electrogoniometer. Six randomized trials, three at zero heel inclination and three at 5 cm positive heel inclination, were measured. Analysis of variance results indicated positive heel inclination of subjects brought about significantly lower anterior pelvic tilt, lumbar lordosis, and sacral base angles when compared with zero heel inclination (p < .01). Clinically, patients with low back pain may be affected by high heel usage because of the reduction of the normal lumbar lordosis.

Systemic and ocular findings in 169 prospectively studied child deaths: retinal hemorrhages usually mean child abuse.

The presence and location of ocular hemorrhages were prospectively studied in 169 randomly selected child deaths referred to a medical examiner. Causes of death in the study group included natural diseases and various injuries involving the head, trunk, and asphyxia. Retinal hemorrhages were identified in 70 cases: 62 head injuries, four central nervous system diseases (but not other natural diseases), and four deaths of undetermined cause. The presence of retinal, peripheral retinal, optic nerve sheath, and intrascleral hemorrhages were strongly associated with head injury as compared to other injuries and natural diseases (Yates corrected P-values < 0.001). Among the head-injured with retinal hemorrhages, nine had a history of severe traumatic event (e.g., an unrestrained rear-seat passenger in high-speed collision) and 53 were victims of inflicted injury (e.g. violent shaking). In the absence of a verifiable history of a severe head injury or life-threatening central nervous system disease, retinal and ocular hemorrhages were diagnostic of child abuse.

The effects of taper on performance in distance runners.

The purpose of this study was to determine if a 7-d systematic reduction in training volume or "taper" could improve distance running performance. Three groups of eight runners were examined: 1) run taper, 2) cycle taper, and 3) control. Training in the run taper group consisted of high-intensity intervals and an 85% reduction in training volume. The cycle taper group performed an equivalent amount of interval training as the run taper group, but each member exercised on a cycle ergometer. Control subjects continued normal training. A self-paced 5-km time trial served as the index of performance. The run taper group decreased 5-km time by 3% (1036.2 +/- 30.6 to 1006.8 +/- 28.2 s, P < 0.005). A significant decrease (P < 0.01) in submaximal oxygen consumption (6%) and calculated caloric expenditure (7%) at a running speed eliciting 80% of VO2max was also evident in the run taper group. Five-km performance and running economy were not altered in the cycle taper or control groups. These findings indicate that 7 d of tapered running improved distance running performance and running economy. A taper regimen of equivalent duration cycle training maintained performance in distance runners.

Relationship between cardiorespiratory fitness and lipoprotein(a) in men and women.

Lipoprotein(a) [Lp(a)] is a distinct lipoprotein of the low density lipoprotein (LDL) class. Research has shown that elevated Lp(a) is an independent risk factor for coronary heart disease (CHD). The purpose of this cross-sectional study was to determine whether fitness was associated with Lp(a) concentrations. Cardiorespiratory (CR) fitness, assessed by maximal treadmill time, percent body fat (hydrodensitometry), body fat distribution (waist/hip ratio), lipoprotein profile and LDL particle size (2-16% gel electrophoresis) were determined in healthy Caucasian men (N = 100) and women (N = 50). As expected, the frequency distribution of Lp(a) was highly skewed with a mean level of 16.9 +/- 19.1 mg.dl-1 (range 0.10-90 mg.dl-1) for men and women combined. Lp(a) was only significantly (P < 0.05) correlated with cholesterol (r = 0.29) in women and LDL-C (r = 0.22) in men. However, after correcting LDL-C for Lp(a) content, the correlation was not significant (r = 0.06). A MANCOVA, controlling for age, across highest and lowest CR fitness quartiles suggest a typical positive influence of improved CR fitness on lipoproteins, body composition, and fat distribution; however, Lp(a) levels were not affected. These data indicate that there is no direct association between plasma Lp(a) and body composition, fat distribution, or CR fitness in healthy men and women.

The effects of static and ballistic stretching on delayed onset muscle soreness and creatine kinase.

The purpose of this study was to determine if static and ballistic stretching would induce significant amounts of delayed onset muscle soreness (DOMS) and increases in creatine kinase (CK). Twenty males were randomly assigned to a static (STATIC) or ballistic stretching (BALLISTIC) group. All performed three sets of 17 stretches during a 90-min period, the only group difference being that STATIC remained stationary during each 60-s stretch while BALLISTIC performed bouncing movements. Subjective ratings of DOMS (scale: 1-10) and serum CK levels were assessed before and every 24 hours post stretching, for 5 days. A repeated measures ANOVA revealed a significant main effect due to time (p < 0.05), with peak soreness occurring at 24 hours after (M = 2.8 +/- 1.6). Surprisingly, a group effect (p < .05) demonstrated that DOMS was significantly greater for STATIC than for BALLISTIC. At 24 hours there was a 62% (p < .05) increase in CK for combined groups. These findings indicate that similar bouts of static and ballistic stretching induce significant increases in DOMS and CK in subjects unaccustomed to such exercise. Furthermore, static stretching induced significantly more DOMS than did ballistic.

Effects of isokinetic soreness-inducing exercise on blood levels of C-reactive protein and creatine kinase.

This study examined whether acute inflammation was the mechanism underlying delayed muscle soreness (DMS) by assessing the effect of soreness-inducing exercise on blood levels of C-reactive protein (CRP), an acute inflammation marker. Sixteen female college students (= 20.6 +/- 2.6 years) performed three sets of 35 isokinetic contractions of the knee flexors and extensors at 120 degrees /set on a Biodex isokinetic dynamometer. Group 1 (N = 8) exercised eccentrically and Group 2 (N = 8) concentrically at an intensity of 80% of a concentric 120 degrees /set peak torque. Pre-exercise and 1, 24, 48 and 72 hours postexercise, DMS of the quadriceps femoris (QF) and hamstrings (HA) were assessed and blood samples were collected for creatine kinase (CK), an indicator of muscle damage, and CRP, which was measured by a radial immunodiffusion procedure. The mean CK values 72 hours postexercise were 14,856 and 360 IU/L for groups 1 and 2, respectively. No significant elevations of CRP occurred in either group. ANOVAs using a split plot factorial design found Group 1 to have significantly larger logarithmic CK elevations, ranked QF soreness, and ranked HA soreness than Group 2. In contrast to myocardial infarct patients and marathon runner investigations, this study did not demonstrate abnormal elevations of CRP when increases in CK were induced. With high-repetition submaximal isokinetic exercise, eccentric contractions induce higher levels of muscle damage and DMS than concentric contractions. Further, the hamstrings are more susceptible to DMS than the quadriceps femoris when eccentric isokinetic exercise is performed at the same relative intensity. J Orthop Sports Phys Ther 1992;16(5):208-214.

Measurement of grip strength: validity and reliability of the sphygmomanometer and jamar grip dynamometer.

Quantitative measurement of grip strength is an important variable when plotting the progress of a hand-injured patient. When utilizing traditional commercially available apparatuses, obtaining meaningful grip strength measurement in these subjects is frequently difficult due to severe deformity, high tissue sensitivity, and low levels of force generated. The purpose of this study was to measure hand grip strength using two instruments having different physical characteristics and units of measurement to determine the reliability of repeated measures with each instrument. Additionally, validity of the sphygmomanometer for strength measurement was established through comparison with the values obtained from measurements using the research-validated Jamar dynamometer. Twenty-nine right hand dominant female college-age subjects volunteered to perform hand grip strength testing. Measurements were taken with a sphygmomanometer and a Jamar dynamometer while utilizing standardized measurement procedures. A Spearman Rho correlation coefficient test utilized in measuring within-instrument reliability showed a high correlation for each instrument at .85 for the sphygmomanometer and .82 for the Jamar dynamometer. Construct validity testing performed to determine validity of the measurements by the sphygmomanometer compared with the Jamar dynamometer produced a .75 correlation. A formula for conversion of the sphygmomanometer scores into Jamar units was developed to enhance reporting of sphygmomanometer scores utilizing the Jamar standard. The study showed that the sphygmomanometer and Jamar dynamometer exhibit good within-instrument reliability. Validity of the sphygmomanometer as a grip measurement device is acceptable and reportable using the conversion formula developed. Therefore, it can be utilized with confidence as essentially equal to the Jamar unit for grip strength measurement. J Orthop Sports Phys Ther 1992;16(5):215-219.

The impact on factory workers of health risk appraisal and counseling in health promotion.

One hundred thirty-six subjects employed at a textile plant in eastern North Carolina participated in a voluntary health risk appraisal (HRA) administration and health screening at the work site. The subjects consisted of 74 whites (73% women and 27% men) and 62 blacks (98% women and 2% men). Six weeks after the HRA administration and health screening, participants received their results at individual counseling sessions conducted by health educators and registered nurses, who presented prevention recommendations derived from HRA and screening results related to select physiological indices and lifestyle behaviors. Six months following the initial intervention, we conducted an identical follow-up screening. Eight months following the initial intervention, we administered a health behavior questionnaire designed to determine the impact of the HRA on select health-related behaviors and subjects' recall level of HRA recommendations. Results of this study indicate that changes in subjects' self-reported health behaviors were related to recommendations presented at counseling sessions. The majority of the subjects accurately recalled HRA recommendations eight months after HRA administration. Ninety-three percent of the employees indicated making at least one positive lifestyle behavioral change, and 50% of the subjects who were referred to a doctor or health professional based on HRA recommendations reported doing so. Risk age did not appear to influence the individual's likelihood of attending the second health screening. Ninety-eight percent of the subjects indicated that they would like a yearly HRA or health screening conducted at the work site, and 88% of the subjects indicated that the HRA results encouraged them to continue practicing healthy behaviors.(ABSTRACT TRUNCATED AT 250 WORDS)

Gastric emptying during 1 h of cycling and running at 75% VO2max.

The purpose of this study was to compare gastric emptying (GE) responses during intense, prolonged cycling and running. It is important to discern whether gastric emptying (GE) responses are exercise-mode specific, since the findings of cycling and running studies are often compared and applied to one another. Ten male biathletes cycled (CY) and ran (R) for 1 h at 75% of their mode-specific VO2max or rested (S) and consumed water (SW, CYW, RW) or a 7% carbohydrate solution (SC, CYC, RC) at a rate of 10 ml.kg-1.h-1 (approximately 180 ml at 0, 15, 30, and 45 min). No differences were found between CYW, CYC, RW, RC, and SC for volume of drink emptied (mean +/- SE) (522.8 +/- 47.9 ml) and GE rate (range, 8.2 +/- 0.9 (RC) to 9.3 +/- 0.6 ml.min-1 (SC]. A mean of 72.7 +/- 5.7% of the total consumed volume was emptied. The GE rate during SW was significantly (P less than 0.05) greater than the other conditions (11.3 +/- 0.4 ml.min-1, 94.0 +/- 1.9% of total consumed volume emptied). Substantial volumes of water and a 7% carbohydrate solution are thus emptied from the stomach during prolonged, intense running and cycling, with no differences in GE between these exercise modes. These data suggest that recommendations concerning GE are reciprocal between running and cycling bouts similar to those in the current study.

The role of anaerobic ability in middle distance running performance.

The purpose of this study was to assess the relationship between anaerobic ability and middle distance running performance. Ten runners of similar performance capacities (5 km times: 16.72, SE 0.2 min) were examined during 4 weeks of controlled training. The runners performed a battery of tests each week [maximum oxygen consumption (VO2max), vertical jump, and Margaria power run] and raced 5 km three times (weeks 1, 2, 4) on an indoor 200-m track (all subjects competing). Regression analysis revealed that the combination of time to exhaustion (TTE) during the VO2max test (r2 = 0.63) and measures from the Margaria power test (W.kg-1, r2 = 0.18; W, r2 = 0.05) accounted for 86% of the total variance in race times (P less than 0.05). Regression analysis demonstrated that TTE was influenced by both anaerobic ability [vertical jump, power (W.kg-1) and aerobic capacity (VO2max, ml.kg-1.min-1)]. These results indicate that the anaerobic systems influence middle distance performance in runners of similar abilities.

Effect of varying the ratio of electrically induced muscle contraction time to rest time on serum creatine kinase and perceived soreness.

Supported in part by a North Carolina Physical Therapy Association Student Research Grant. The purpose of this study was to determine whether there were differences in the amount of muscle soreness and serum creatine kinase (CK) produced when ratios of electrically induced muscle contraction time to rest time were varied. Fifteen subjects were randomly assigned to one of three groups, each receiving 10, 15-second electrically induced isometric contractions of the quadriceps femoris muscle with rest periods of 10, 30, and 50 seconds between contractions, respectively. The intensity of the contractions were maintained at 30 percent of an individual's maximum voluntary isometric contraction (MVC). Blood samples for serum CK activity, an indicator of muscle damage, and perceived soreness were collected pretreatment, 24, 48, and 72 hours following the single treatment session. Significant increases in the serum CK and perceived soreness ratings were observed in all groups. Postexercise serum CK increases were found to be significantly different between the 10 seconds and the 30-seconds and 50-seconds rest period groups. Clinically, muscle soreness may result from initial trials of neuromuscular electrical stimulation (NMES) with peak amplitudes sufficient to produce contractions equivalent to 30 percent of the MVC. Contraction time to rest ratios of NMES may influence the amount of muscle damage produced. J Orthop Sports Phys Ther 1991,13(6):310-315.

Trend analysis for repeated measures designs.

This paper outlines a method of analysis that is well-suited to repeated measures designs. This method uses polynomial functions of time to characterize an outcome variable measured at several distinct time points on the same subjects. Profiles for different treatment groups may be compared using the appropriate interaction terms in an analysis of variance table. The method is illustrated with data from two recent studies.

Arm-span, height, and age in black and white women.

This paper presents the results of an anthropometric study of 293 Black and 298 White females, ages 35-89 years, who were healthy, non-institutionalized residents of North Carolina. All subjects were measured for arm-span and height. Correlations of the two measures were obtained for each race independently. Additionally, age as a factor in arm-span and height correlation for the two races was examined. Correlation of arm-span and height for Black subjects was 0.852 and for White subjects was 0.903. Age and height correlation for White women was -0.237 and for Black women was -0.114. Age and arm-span correlation for White women was -0.167 and for Black women was -0.106. Separate equations for estimation of height based on age and arm-span were developed for women of the two races: height of White women (cm) = 29.58-(0.04 x age) + (0.81 x arm-span); height of Black women (cm) = 37.72-(0.01 x age) + (0.73 x arm-span).

Motorcyclist fatalities and the repeal of mandatory helmet wearing laws.

Previous studies had estimated that repeal of mandatory helmet wearing laws resulted in increases in the number of fatalities ranging from nearly 40% to essentially zero. This study was performed to determine more definitively the influence on motorcyclist fatalities of these repeals. After repeal, motorcyclist fatalities increased more in the states which repealed their laws than in those which did not in 24 cases out of 26, with the 95% confidence interval for the average effect being 25 +/- 6%. It is therefore concluded that repeals of mandatory helmet wearing laws for motorcyclists were followed by substantial increases in motorcyclist fatalities.