The mediating role of intention and stages of change in physical activity among adults with physical disabilities: an integrative framework

The study's purpose was to identify the mediating role of intention and the stages of change (SOC) in physical activity (PA) over a 6-month period using two models (theory of planned behavior [TPB] and TPB/SOC). Participants were 143 adults with physical disabilities (70.68% response rate; M age = 46.03). The TPB constructs, SOC (time 1), and PA (time 2) were assessed using standardized self-report questionnaires. Based on path analyses, attitude had the highest effect on intention and SOC followed by perceived behavioral control within both well-fit models. The variance in PA explained by the first (TPB) and second (TPB/SOC) models was 16% and 28% respectively. In the just identified model of TPB/SOC, the direct effect of SOC on physical activity remained strong (gamma(soc.pa) = .45) and SOC approached full mediation through attitude. Health promotion interventions need to include both intention and behavior elements (SOC) reinforcing increased PA value and barrier elimination.     

Interleukin-6 and Delayed Onset Muscle Soreness Do Not Vary During the Menstrual Cycle

The purpose of this study was to determine if a difference in interleukin-6 (IL-6) and delayed onset muscles soreness (DOMS) exists in two different phases of the menstrual cycle. Nine runners performed one 75-min high-intensity interval running session during the early follicular (EF) phase and once during the midluteal (ML) phase of the menstrual cycle. Estrogen and progesterone levels were significantly reduced in the EF phase when compared to the ML phase. IL-6 levels increased from pre- to postexercise in the EF and ML phases (p < .001). There was no relationship between the IL-6 level and DOMS. The results suggest that menstruating female runners need not vary training throughout the month to reduce DOMS.     

Accelerometer and GPS Data to Analyze Built Environments and Physical Activity

ABSTRACT

Purpose: Most built environment studies have quantified characteristics of the areas around participants’ homes. However, the environmental exposures for physical activity (PA) are spatially dynamic rather than static. Thus, merged accelerometer and global positioning system (GPS) data were utilized to estimate associations between the built environment and PA among adults. Methods: Participants (N = 142) were recruited on trails in Massachusetts and wore an accelerometer and GPS unit for 1–4 days. Two binary outcomes were created: moderate-to-vigorous PA (MVPA vs. light PA-to-sedentary); and light-to-vigorous PA (LVPA vs. sedentary). Five built environment variables were created within 50-meter buffers around GPS points: population density, street density, land use mix (LUM), greenness, and walkability index. Generalized linear mixed models were fit to examine associations between environmental variables and both outcomes, adjusting for demographic covariates. Results: Overall, in the fully adjusted models, greenness was positively associated with MVPA and LVPA (odds ratios [ORs] = 1.15, 95% confidence interval [CI] = 1.03, 1.30 and 1.25, 95% CI = 1.12, 1.41, respectively). In contrast, street density and LUM were negatively associated with MVPA (ORs = 0.69, 95% CI = 0.67, 0.71 and 0.87, 95% CI = 0.78, 0.97, respectively) and LVPA (ORs = 0.79, 95% CI = 0.77, 0.81 and 0.81, 95% CI = 0.74, 0.90, respectively). Negative associations of population density and walkability with both outcomes reached statistical significance, yet the effect sizes were small. Conclusions: Concurrent monitoring of activity with accelerometers and GPS units allowed us to investigate relationships between objectively measured built environment around GPS points and minute-by-minute PA. Negative relationships between street density and LUM and PA contrast evidence from most built environment studies in adults. However, direct comparisons should be made with caution since most previous studies have focused on spatially fixed buffers around home locations, rather than the precise locations where PA occurs.     

Heart rate prescribed walking training improves cardiorespiratory fitness but not glycaemic control in people with type 2 diabetes

Abstract

In this study, we examined the effects of a supervised, heart rate intensity prescribed walking training programme on cardiorespiratory fitness and glycaemic control in people with type 2 diabetes mellitus. After receiving local ethics approval, 27 individuals (21 males, 6 females) with type 2 diabetes were randomly assigned to an experimental (“walking”) or control group. Participants completed a Balke-Ware test to determine peak heart rate, peak oxygen consumption ([Vdot]O_2peak), and peak gradient. The walking group then completed a 7-week (four sessions a week) supervised, heart rate prescribed walking training programme, whereas the control group continued daily life. After training, participants completed another Balke-Ware test. Fasting blood glucose and glycosylated haemoglobin were measured at rest. The results showed that walking training elicited 80% (s = 2) of peak heart rate and a rating of perceived exertion of 11 (s = 1). Peak heart rate and [Vdot]O_2peak were higher in the walking than in the control group after training (P < 0.05). Based on the peak gradient before training, the respiratory exchange ratio was significantly lower (P < 0.05) and there was a strong trend for [Vdot]O₂ (P = 0.09) and heart rate (P = 0.09) to be lower after training at the same gradient in the walking compared with the control group. These improvements increased walking peak gradient by 5 min (s = 4 min) compared with the control (P < 0.05). There was no change in fasting blood glucose or glycosylated haemoglobin after training. Despite no change in glycaemic control, heart rate prescribed walking improved peak and sub-maximal cardiorespiratory responses. The beneficial adaptations support the use of heart rate monitoring during walking in people with type 2 diabetes mellitus.     

The Impact of Prior Counseling on Predictors of College Counseling Center Use

Path analyses revealed that one's tendency to conceal distressing information, social support, psychological distress, and attitudes toward seeking help predicted intended use of counseling services for college students who had and had not previously been in counseling. Prospective analyses revealed that attitudes toward seeking help predicted actual use of the campus counseling center. These findings have implications for campus outreach programs and in‐session work with clients.     

Professional Ethics in the College and University Science Curriculum

Scientific ethics is a subset of professional ethics, the special rules of conduct adopted by those engaged in one of the pursuits regarded as professions, such as law, medicine, engineering and science. Professional ethics derive from a moral ideal based on service. This ideal leads to a pair of bargains: an internal bargain that defines the internal code of practice within the profession, and an external bargain that defines the relationship between the profession and society. This article develops the internal and external bargains that are the basis of scientific ethics from both an historical and a philosophical perspective and makes suggestions as to how the teaching of scientific ethics can be integrated into the undergraduate curriculum.     

Creatine kinase activity weakly correlates to volume completed following upper body resistance exercise

In the current study, we examined the relationship between serum creatine kinase (CK) activity following upper body resistance exercise with a 1- or 3-min rest between sets. Twenty men performed two sessions, each consisting of four sets with a 10-repetition maximum load. The results demonstrated significantly greater volume for the 3-min condition (M = 4156 kg, SD = 867, for 3 min; vs. M = 3503 kg SD = 759, for 1 min; p < .001), with no significant differences in delta CK activity between conditions (p = .574). Nevertheless, there was a weak correlation between the delta CK activity and total volume of exercise completed (r = .55 with a 1-min rest, and r = .45 with a 3-min rest). Therefore, the volume following upper body resistance exercise correlates weakly with serum CK levels, irrespective of rest interval length between sets.     

Transport and shear in a microfluidic membrane bilayer device for cell culture

Microfluidic devices have been established as useful platforms for cell culture for a broad range of applications, but challenges associated with controlling gradients of oxygen and other soluble factors and hemodynamic shear forces in small, confined channels have emerged. For instance, simple microfluidic constructs comprising a single cell culture compartment in a dynamic flow condition must handle tradeoffs between sustaining oxygen delivery and limiting hemodynamic shear forces imparted to the cells. These tradeoffs present significant difficulties in the culture of mesenchymal stem cells (MSCs), where shear is known to regulate signaling, proliferation, and expression. Several approaches designed to shield cells in microfluidic devices from excessive shear while maintaining sufficient oxygen concentrations and transport have been reported. Here we present the relationship between oxygen transport and shear in a "membrane bilayer" microfluidic device, in which soluble factors are delivered to a cell population by means of flow through a proximate channel separated from the culture channel by a membrane. We present an analytical model that describes the characteristics of this device and its ability to independently modulate oxygen delivery and hemodynamic shear imparted to the cultured cells. This bilayer configuration provides a more uniform oxygen concentration profile that is possible in a single-channel system, and it enables independent tuning of oxygen transport and shear parameters to meet requirements for MSCs and other cells known to be sensitive to hemodynamic shear stresses.     

Perspectives on pedagogical change: instructor and student experiences of a newly implemented undergraduate engineering dynamics curriculum*

Engineering education has been slow to adopt research-based educational innovations. Few prior works on such adoption have investigated the combined classroom experiences of instructors and students when such innovations are being implemented. Therefore, this work focuses on the lived experiences of an instructor and her students when adopting an active, blended, and collaborative learning environment, known as Freeform, in a second-year dynamics course. Weekly reflections from the instructor were processed alongside student interviews using Thematic Analysis to discern prominent themes in their perspectives for comparison and discussion. The results indicate that the instructor navigated internal tensions between her previous instructional preferences and the philosophy and resources of Freeform. Similarly, students had to adapt to this new philosophy and suite of resources that were uncommon for their institution. Ultimately, this work highlights the contextual natures of teaching and learning, and how situational factors can influence educational innovation.