Publications by authors named "Jaci L Van Heest"

The electrodermal activity (EDA) is a useful tool for assessing skin sympathetic nervous activity. Using spectral analysis of EDA data at rest, we have previously found that the spectral band which is the most sensitive to central sympathetic control is largely confined to 0.045 to 0.

View Article and Find Full Text PDF

This observational case study examined the association of inter- and intraday energy intake and exercise energy expenditure with bone health, menstrual status and hematological factors in a female triathlete. The study spanned 7 months whereby energy intake and exercise energy expenditure were monitored three times (13 d); 16 blood samples were taken, urinary hormones were assessed for 3 months, and bone mineral density was measured twice. Energy availability tended to be sustained below 30 kcal/kg FFM/d and intraday energy intake patterns were often "back-loaded" with approximately 46% of energy consumed after 6 p.

View Article and Find Full Text PDF

Opiate dependence is a significant public health concern linked to poor quality of life, comorbid psychiatric disorders, and high costs to society. Current opiate agonist treatments are an effective but limited intervention. Adjunctive interventions could improve and augment opiate agonist treatment outcomes, including drug abstinence, quality of life, and physical health.

View Article and Find Full Text PDF

Objective: A polymorphism (-786 T>C) in the promoter region of the endothelial nitric oxide synthase gene (eNOS) has important functional characteristics. We examined the influence of eNOS -786 T>C (rs2070744) on the BP and NO response to acute dynamic exercise.

Methods: Subjects (n=49, 43.

View Article and Find Full Text PDF

The purpose of this study was twofold: (1) to determine if gastrointestinal hormones, associated with energy intake and energy balance, are altered in exercising women with hypothalamic amenorrhea and (2) to assess the association between gastrointestinal hormones and behavioural indicators of subclinical disordered eating in exercising women with hypothalamic amenorrhea. This cross-sectional study analyzed serum ghrelin, peptide YY (PYY), glucagon-like peptide-1 (GLP-1), menstrual status (by E1G and PdG), resting energy expenditure (REE), and subclinical eating behaviours in sedentary ovulatory (SedOv), exercising ovulatory (ExOv), and exercising amenorrheic (ExAmen) women. Groups were similar with respect to age (23.

View Article and Find Full Text PDF

Background: The metabolic syndrome (Msyn) affects about 40% of those with hypertension. The Msyn and hypertension have a common pathophysiology. Exercise is recommended for their treatment, prevention and control.

View Article and Find Full Text PDF

Background: We examined the response of bone turnover markers and indices of energy status after 2 weeks of oral contraceptive (OC) therapy in premenopausal women with exercise-associated menstrual disturbances (EAMD).

Study Design: Six women with EAMD received one 28-day cycle of a triphasic OC containing 180-250 mcg norgestimate/25 mcg ethinyl estradiol (EAMD+OC) and six were controls (EAMD controls). Bone turnover markers amino-terminal propeptide of Type I procollagen and serum carboxy-terminal telopeptides of Type I collagen (PINP and SCTX-I) were assessed at baseline and after 2 weeks of OC therapy (EAMD+OC) or after a 30-day monitoring period (EAMD controls).

View Article and Find Full Text PDF

Competitive female athletes face many challenges unlike their recreationally active counterparts. As sport has advanced for girls and women, the physical, psychologic, and nutritional demands force female athletes to develop optimal strategies for competitive success. Sports medicine professionals must consume volumes of research investigating issues regarding competitive female athletes.

View Article and Find Full Text PDF

Alterations in resting energy expenditure and metabolic hormones (energy conservation) are evident in increasing magnitude across a continuum of increasing severity of clinical menstrual disturbances, including luteal-phase defects, anovulation, and amenorrhea in exercising women. These data provide further evidence of the tight association between energy balance and reproduction and suggest that subtle declines in energy availability can produce clinically recognized menstrual disturbances.

View Article and Find Full Text PDF

Purpose: The primary purpose of this study was to determine whether tests performed at the National Hockey League (NHL) Combine could distinguish draft status (ie, the round selected). A secondary aim was to provide performance ranges and percentiles for each of the dependent variables.

Methods: A retrospective, cross-sectional study design was used with performance data and draft order from 2001, 2002, and 2003 Combine participants.

View Article and Find Full Text PDF

Purpose: The purpose of this investigation was to determine the effects of 3 wk of L-carnitine L-tartrate (LCLT) supplementation and post-resistance-exercise (RE) feeding on hormonal and androgen receptor (AR) responses.

Methods: Ten resistance-trained men (mean+/-SD: age, 22+/-1 yr; mass, 86.3+/-15.

View Article and Find Full Text PDF

Open-water swimming (5, 10, and 25 km) has many unique challenges that separate it from other endurance sports, like marathon running and cycling. The characteristics of a successful open-water swimmer are unclear. The purpose of this study was to determine the physical and metabolic characteristics of a group of elite-level open-water swimmers.

View Article and Find Full Text PDF

This study assessed body composition of Division I football players (n = 69) and compared the findings with previously reported data to ascertain whether the increase in player total body mass that has been observed over the past 10 years has been accompanied by an increase in body fat. Body composition was determined by hydrostatic weighing and the measurement of skinfold thicknesses. Total body mass, skinfold thicknesses, and body fat were greater in the current players than in players in studies conducted in the early 1980s and early 1990s.

View Article and Find Full Text PDF

The purposes of this study were to characterize measures of fluid intake and perception of thirst in women over a 6-week period of exercise-heat acclimation and outdoor training and examine if this lengthy acclimation period would result in changes in fluid intake that differ from those previously reported in men utilizing a shorter acclimation protocol of 8-10 days. Voluntary water intake (11-17 degrees C) and perception of thirst were measured in a group of 5 women (21-26 yr) undergoing exercise-heat acclimation for 90 min/day, 3 days/wk (36 degrees C, rh 50-70%) and outdoor training 3 days/wk for 6 weeks. Decreased drinking during acclimation was characterized by a decrease in the number of drinks (35 +/- 10 to 17 +/- 5; p <.

View Article and Find Full Text PDF

Rationale: Medications combining hydrocodone bitartrate and non-steroidal anti-inflammatory agents appear more beneficial than anti-inflammatory medications alone in treating pain and inflammation from acute soft tissue trauma, but opiate side effects may include sedation and impaired cognitive and motor performance.

Objective: Performance on complex cognitive and motor tasks was evaluated in healthy subjects with exercise-induced muscle damage who were treated with a hydrocodone-ibuprofen combination, ibuprofen alone, or placebo.

Methods: This double-blind, randomized, placebo-controlled, repeated-dose clinical trial compared the effects of hydrocodone bitartrate (7.

View Article and Find Full Text PDF

When prolonged, excessive training stresses are applied concurrent with inadequate recovery, performance decrements and chronic maladaptations occur. Known as the overtraining syndrome (OTS), this complex condition afflicts a large percentage of athletes at least once during their careers. There is no objective biomarker for OTS and the underlying mechanism is unknown.

View Article and Find Full Text PDF

A PHP Error was encountered

Severity: Warning

Message: fopen(/var/lib/php/sessions/ci_session7lal19d9dok6g7a206106eqe7pb9smm3): Failed to open stream: No space left on device

Filename: drivers/Session_files_driver.php

Line Number: 177

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)

Filename: Session/Session.php

Line Number: 137

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once