Increased fatigability and impaired skeletal muscle microvascular reactivity in adults with obstructive sleep apnea: a cross-sectional study.

Background: Sympathetic nervous system hyperactivity and chronic intermittent nocturnal hypoxia in individuals with obstructive sleep apnea (OSA) predispose them to microvascular impairment, which may contribute to increased daytime muscle fatigue. This study aimed to assess microvascular reactivity of the skeletal muscle, examine fatigability, and determine the relationship between fatigability and microvascular reactivity in adults with OSA.

Methods: Twenty-six participants were allocated into two groups-those with OSA and those without i.

Errors in soil maps: The need for better on-site estimates and soil map predictions.

High-quality soil maps are urgently needed by diverse stakeholders, but errors in existing soil maps are often unknown, particularly in countries with limited soil surveys. To address this issue, we used field soil data to assess the accuracy of seven spatial soil databases (Digital Soil Map of the World, Namibian Soil and Terrain Digital Database, Soil and Terrain Database for Southern Africa, Harmonized World Soil Database, SoilGrids1km, SoilGrids250m, and World Inventory of Soil Property Estimates) using topsoil texture as an example soil property and Namibia as a case study area. In addition, we visually compared topsoil texture maps derived from these databases.

Walking endurance, muscle oxygen extraction, and perceived fatigability after overground locomotor training in incomplete spinal cord injury: A pilot study.

The purpose of this study was to examine the effects of overground locomotor training (OLT) on walking endurance and gastrocnemius oxygen extraction in people with chronic cervical motor-incomplete spinal cord injury (SCI). Prospective single-arm pre-post pilot study. Human Performance Research Laboratory.

Mobile phone use is associated with higher smallholder agricultural productivity in Tanzania, East Africa.

Mobile phone use is increasing in Sub-Saharan Africa, spurring a growing focus on mobile phones as tools to increase agricultural yields and incomes on smallholder farms. However, the research to date on this topic is mixed, with studies finding both positive and neutral associations between phones and yields. In this paper we examine perceptions about the impacts of mobile phones on agricultural productivity, and the relationships between mobile phone use and agricultural yield.

Modifying connectivity to promote state change reversal: the importance of geomorphic context and plant-soil feedbacks.

Alternative states maintained by feedbacks are notoriously difficult, if not impossible, to reverse. Although positive interactions that modify soil conditions may have the greatest potential to alter self-reinforcing feedbacks, the conditions leading to these state change reversals have not been resolved. In a 9-yr study, we modified horizontal connectivity of resources by wind or water on different geomorphic surfaces in an attempt to alter plant-soil feedbacks and shift woody-plant-dominated states back toward perennial grass dominance.

Effect of overground locomotor training on ventilatory kinetics and rate of perceived exertion in persons with cervical motor-incomplete spinal cord injury.

Study Design: Pre-post, pilot study.

Objectives: To characterize ventilatory () responses to exercise following warm-up walking in individuals with chronic incomplete spinal cord injury (iSCI) during constant work rate (CWR) exercise. Secondarily, to investigate and tidal volume () variability, and ratings of perceived exertion (RPE) before and after overground locomotor training (OLT).

Left Ventricular Function Before and After Aerobic Exercise Training in Women With Pulmonary Arterial Hypertension.

Background: Pulmonary arterial hypertension (PAH) is a chronic debilitating illness. The effects of vigorous aerobic exercise training (AET) on heart function in PAH are poorly understood.

Methods: Eighteen women with PAH (aged 56.

Resistance training does not alter same-day sleep architecture in institutionalized older adults.

Sleep disturbance is a common symptom in institutionalized older adults that reduces their quality of life and may contribute to progression of cognitive impairment. While we found that a 7-week combination of resistance training, walking and social activity significantly improved sleep in institutionalized older adults compared with a usual care control group, no one to our knowledge has determined the acute effects of resistance training on same-day sleep in this population. Given the effort required to promote exercise adherence in institutionalized older adults and to obtain a positive training effect, understanding of the acute effects of resistance training on same-day sleep architecture should be elucidated, especially with respect to unintended consequences.

Fatigability, oxygen uptake kinetics and muscle deoxygenation in incomplete spinal cord injury during treadmill walking.

Purpose: The purpose of the present study was to characterize hypothesized relationships among fatigability and cardiorespiratory fitness in individuals with chronic motor-incomplete SCI (iSCI) during treadmill walking. The theoretical framework was that exacerbated fatigability would occur concomitantly with diminished cardiorespiratory fitness in people with iSCI.

Methods: Subjects with iSCI (n = 8) and an able-bodied reference group (REF) (n = 8) completed a 6-min walking bout followed by a walking bout of 30-min or until volitional exhaustion, both at a self-selected walking speed.

Leptin, Leptin Soluble Receptor, and the Free Leptin Index following a Diet and Physical Activity Lifestyle Intervention in Obese Males and Females.

Leptin (LEP) is associated with appetite regulation and metabolism. Concentration is linear with adiposity, suggesting LEP resistance. LEP circulates freely and bound with its soluble receptor (sOB-r); the ratio is the free leptin index (FLI), an index of leptin resistance; lower FLI suggests reduced biological action.

Effects of Overground Locomotor Training on Walking Performance in Chronic Cervical Motor Incomplete Spinal Cord Injury: A Pilot Study.

Objective: To determine the effects of a novel overground locomotor training program on walking performance in people with chronic cervical motor incomplete spinal cord injury (iSCI).

Design: Before-after pilot study.

Setting: Human performance research laboratory.

Assessment of Cardiopulmonary Responses to Treadmill Walking Following Gastric Bypass Surgery.

Background: Studies that have evaluated cardiopulmonary responses to exercise within the first few months of bariatric surgery have utilized cycle ergometry. However, walking is the most commonly reported mode of both pre- and post-operative PA. The divergent cardiopulmonary responses and metabolic costs of weight-bearing (walking) and non-weight-bearing (cycling) exercises warrant examination of the effects of bariatric surgery on cardiopulmonary responses during walking.

Strength training and light physical activity reduces the apnea-hypopnea index in institutionalized older adults.

Objectives: To determine the effect of 7 weeks of resistance training and walking on the apnea-hypopnea index (AHI) in institutionalized older adults compared with a usual care control group.

Design: Secondary analysis of data from a randomized controlled trial.

Setting: Ten nursing and 3 assisted living facilities in Arkansas.

Ecological site‐based assessments of wind and water erosion: informing accelerated soil erosion management in rangelands.

Accelerated soil erosion occurs when anthropogenic processes modify soil, vegetation, or climatic conditions causing erosion rates at a location to exceed their natural variability. Identifying where and when accelerated erosion occurs is a critical first step toward its effective management. Here we explored how erosion assessments structured in the context of ecological sites (a land classification based on soils, landscape setting, and ecological potential) and their vegetation states (plant assemblages that may change due to management) can inform systems for reducing accelerated soil erosion in rangelands.

Regional signatures of plant response to drought and elevated temperature across a desert ecosystem.

The performance of many desert plant species in North America may decline with the warmer and drier conditions predicted by climate change models, thereby accelerating land degradation and reducing ecosystem productivity. We paired repeat measurements of plant canopy cover with climate at multiple sites across the Chihuahuan Desert over the last century to determine which plant species and functional types may be the most sensitive to climate change. We found that the dominant perennial grass, Bouteloua eriopoda, and species richness had nonlinear responses to summer precipitation, decreasing more in dry summers than increasing with wet summers.

Comparison of physiological responses and performance between mountain bicycles with differing suspension systems.

Purpose: This study compared the metabolic and performance effects of riding front-only suspension (FS) and front-and-rear suspension (FRS) mountain bicycles on an off-road course that simulated competitive cross-country race conditions (>105 min in duration, with ∼70% of time spent riding uphill).

Methods: Seven competitive mountain bikers (73.8 ± 7.

Rangeland and pasture monitoring: an approach to interpretation of high-resolution imagery focused on observer calibration for repeatability.

Collection of standardized assessment and monitoring data is critically important for supporting policy and management at local to continental scales. Remote sensing techniques, including image interpretation, have shown promise for collecting plant community composition and ground cover data efficiently. More work needs to be done, however, evaluating whether these techniques are sufficiently feasible, cost-effective, and repeatable to be applied in large programs.

Spatial and temporal variability of plant-available water in calcium carbonate-cemented soils and consequences for arid ecosystem resilience.

Increased variability in precipitation, including frequency of drought, is predicted for many arid and semiarid regions globally. The ability of soils to retain water can increase resilience by buffering vegetation communities against precipitation extremes. Little is known, however, about water retention by carbonate-cemented soil horizons, which occur extensively in arid and semiarid ecosystems.

Evaluation of a 6-month multi-disciplinary healthy weight management program targeting urban, overweight adolescents: effects on physical fitness, physical activity, and blood lipid profiles.

This study evaluated preliminary physical fitness, physical activity, and blood lipid profile data obtained from overweight adolescents upon enrolling in a healthy weight management program and following 6 months of program participation. One hundred and sixty-eight participants (13.4+/-1.

Participation in 150 min/wk of moderate or higher intensity physical activity yields greater weight loss after gastric bypass surgery.

Background: The American College of Sports Medicine's position stand on weight loss and prevention of weight regain in adults has suggested that overweight adults should participate in a minimum of 150 min/wk of moderate intensity physical activity (PA). This study compared the 3-, 6-, and 12-month postoperative weight loss between gastric bypass surgery (GBS) patients who met or exceeded the recommended 150 min/wk of moderate or higher PA and those not meeting the recommendation.

Methods: The self-administered short version of the International Physical Activity Questionnaire was used to assess moderate or higher intensity PA participation at 3 (n = 178), 6 (n = 128), and 12 months (n = 209) after GBS.

Consumption of an oral carbohydrate-protein gel improves cycling endurance and prevents postexercise muscle damage.

Investigators have reported improved endurance performance and attenuated post-exercise muscle damage with carbohydrate-protein beverages (CHO+P) versus carbohydrate-only beverages (CHO). However, these benefits have been demonstrated only when CHO+P was administered in beverage-form, and exclusively in male subjects. Thus, the purposes of this study were to determine if an oral CHO+P gel improved endurance performance and post-exercise muscle damage compared to a CHO gel, and determine if responses were similar between genders.

Global desertification: building a science for dryland development.

In this millennium, global drylands face a myriad of problems that present tough research, management, and policy challenges. Recent advances in dryland development, however, together with the integrative approaches of global change and sustainability science, suggest that concerns about land degradation, poverty, safeguarding biodiversity, and protecting the culture of 2.5 billion people can be confronted with renewed optimism.

Land management in the American southwest: a state-and-transition approach to ecosystem complexity.

State-and-transition models are increasingly being used to guide rangeland management. These models provide a relatively simple, management-oriented way to classify land condition (state) and to describe the factors that might cause a shift to another state (a transition). There are many formulations of state-and-transition models in the literature.