Biomedical subjects

Elizabeth Weiss

Publications and source records attributed to Elizabeth Weiss.

6 recordsLinked to original sources

PubMed2006

Outcomes of an aquatic exercise program including aerobic capacity, lactate threshold, and fatigue in two individuals with multiple sclerosis.

BACKGROUND AND PURPOSE: Fatigue in individuals with multiple sclerosis (MS) may be exacerbated by poor cardiovascular fitness. Although aqua aerobic exercise is often recommended, little research has been conducted on the efficacy of aqua aerobic exercise in improving cardiovascular fitness in patients with MS. The purpose of this case report is to describe changes in cardiovascular fitness and fatigue for 2 people with MS following an aqua aerobics class. CASE DESCRIPTIONS: The participants were 2 females, both with MS for over 10 years and mild disability. Participant A (40 years old and EDSS = 2.5/10) reported fatigue, numbness in her hands and feet, and occasional blurred vision. Participant B (51 years old and EDSS = 3.0/10) reported the same problems as Participant A plus stiffness in her right lower extremity. The participants performed aqua aerobics at an intensity equivalent to their lactate threshold twice a week for 8 weeks. Lactate threshold is the exercise intensity just prior to the accumulation of blood lactate during graded exercise. OUTCOMES: A graded exercise test (with measurements of gas exchange) and a test of fatigue were administered before and after the intervention. Initially, both participants had poor cardiovascular fitness as demonstrated by their low peak oxygen consumption (VO2peak) and low lactate threshold (LT). After the intervention, both participants achieved a higher peak workload (their VO2peak increased) and they could sustain a higher submaximal workload without accumulation of acid substances causing fatigue (their LT increased). Changes in fatigue following the intervention were equivocal with Participant A reporting decreased fatigue and Participant B reporting no change. SUMMARY: This report describes the use of exercise testing to guide clinical decision making for dosing of an aqua aerobic fitness intervention and illustrates positive effects of the intervention on cardiovascular fitness in 2 people with MS.

Adult↗

PubMed2005

Humeral cross-sectional morphology from 18th century Quebec prisoners of war: Limits to activity reconstruction.

This study uses measures of cross-sectional robusticity and asymmetry (based on humeral areal and inertial cross-sectional components) to test a prediction from bone remodeling theory that a physically active 18th century Quebec prisoner of war sample (N = 25) should have more robust and asymmetrical humeri than a nonphysically active 20th century New Mexico suburbanite sample (N = 27). Narrative accounts document that prisoners of war engaged in labor-intensive activities, and these activities were confirmed by observations of osteoarthritis and other pathologies. The suburbanite sample, for the most part, did not engage in such activities. The prisoners had higher levels of pathology than the suburbanites (e.g., 80% vs. 22% osteoarthritis; F = 17.95, P < 0.01). For robusticity, the populations did not differ significantly in total area, cortical area, moment areas of inertia about the mediolateral plane, or polar moment area of inertia. The Quebec prison sample did have significantly higher values for moment areas of inertia about the anteroposterior plane. For asymmetry, the populations did not differ in any values (total area, cortical area, moment areas of inertia about the mediolateral plane, moment areas of inertia about the anteroposterior plane, or polar moment of inertia). Thus, examinations of cross-sectional robusticity and asymmetry failed to conclusively confirm the hypothesis that intensive labor leads to changes in humeral morphology. Possible explanations for the lack of differences are discussed, such as poor diet impeding bone remodeling. Nevertheless, the one significant finding suggests that cross-sectional shape is more useful in reconstructing activity patterns than amount of bone in a cross section. Results from this study join those from other recent investigations to suggest that additional controls are required before cross-sectional differences may be confidently attributed to activity patterns.

Anatomy, Cross-Sectional↗

PubMed2004

Understanding muscle markers: lower limbs.

Musculoskeletal markers are frequently used to reconstruct past lifestyles and activity patterns. Yet the reliability of muscle marker measurements has been called into question because they may be confounded by body size. In this study, an aggregate muscle marker variable was calculated using 20 insertion sites (14 femoral, 6 tibial), and I examined their effects on lower limb size (as a proxy for body size), age, and sex. Analyses were made of a sample of 77 (57 males, 20 females) Native British Columbians (3,500-1,500 years BP) and 18th century Quebec prisoners. Muscle markers were measured using two-point observer rating scales; size was measured by standard methods; and age and sex were determined through pelvic, cranial, and dental morphology. Lower limb muscle markers correlated with: age, r=0.61; lower limb size, r=0.52; and sex, r=0.49; P <0.001. Older individuals had higher muscle marker scores, as did larger individuals and males. Based on partial correlations and regression analyses, age was the best overall predictor of lower limb muscle markers.

Adolescent↗

PubMed2003

Understanding muscle markers: aggregation and construct validity.

Musculoskeletal markers are frequently used to reconstruct past lifestyles and activity patterns. Yet, the reliability of muscle marker measurements has been called into question because they allegedly fail to correlate with cross-sectional properties and exercise patterns, and are confounded by body size. In this study, the principle of aggregation was used to sum muscle markers over 7 insertion sites (4 humeral, 2 radial, and 1 ulnar) and examine the effects on them of body size, age, sex, and cross-sectional properties. Analyses were made of a sample of 91 (66 males, 25 females) Native British Columbians (3500-1500 years BP) and 18th century Quebec prisoners. Muscle markers were measured using three-point observer rating scales; size was measured by standard methods; age and sex were determined through pelvic, cranial, and dental morphology; and cross-sectional properties were calculated from radiographs. Whereas any single muscle marker component failed to correlate with age, size, sex, or cross-sections, aggregate muscle marker correlated with: age, r = 0.49; size, r = 0.38; sex, r = 0.40; and, cross-sections, r = 0.38; P < 0.001. Older individuals had greater muscle markers, as did larger individuals, males, and those with more robust cross-sections. Based on partial correlations and regression analyses, age was the best overall predictor of aggregate muscle marker.

Adult↗

PubMed2003

Effects of rowing on humeral strength.

This study used an aggregate measure of robusticity (based on humeral areal and inertial cross-sectional components) to test the hypothesis that rowing on oceans led to more robust humeri than did rowing on rivers or not rowing at all. Results confirmed the hypothesis that male ocean-rowers had more robust humeri than did male river-rowers or nonrowers. However, although the females from the ocean-rowing populations did not row, they averaged more robust humeri than did females from the non-ocean-rowing populations. Males averaged greater robusticity than did females. The robusticity of ocean-rowing populations, therefore, does not seem to be due solely to bone remodeling resulting from strenuous rowing. Humeral robusticity is difficult to attribute to specific activities because, in humans, upper limbs are utilized for many activities. Some populations may have more robust humeri because certain environments require greater overall activity levels in order to survive.

Adaptation, Biological↗

PubMed2001

Kennewick Man's Funeral: The Burying of Scientific Evidence.

Kennewick Man, an early Holocene (9,000 years old) skeleton found in Washington State in 1996, has been a lightening rod for political discussion. Due to his alleged Caucasoid features, Kennewick Man controversially called into question who first peopled the Americas. A projectile point lodged in his hip also catapulted him to celebrity status. Spared the quick (within ninety days after an inquiry) repatriation typically re- quired under the 1990 federal Native American Graves Protection and Repatriation Act (NAGPRA), Kennewick Man was fully examined by a team of scientists chosen by the government who were forbidden to discuss their findings. Although the team concluded that Kennewick Man has cranial features associated with both Caucasoids and modern Native Americans, he is considered mainly to resemble modern Japanese Ainu, Polynesians, and Southeast Asians, as are other early Amerindian finds. Despite the resolution of early controversies, Kennewick Man continues as a symbol of the ideology of repatriation. In this article, I review the evidence for my belief that, taken to an extreme, the demand to bury aboriginal skeletons, not only in America but also around the world, poses a potentially serious impediment to scientific enquiry.

Journal Article↗