The Association of Stair Climbing Behaviors With Hazard of All-Cause Mortality in Adults With or At Risk of Knee Osteoarthritis.

OBJECTIVE: To investigate the association of stair climbing difficulty and stair climbing frequency with the risk of all-cause mortality over 13 years in adults with or at high risk for knee OA. METHODS: We used data from the Osteoarthritis Initiative (OAI), a prospective cohort study of community-dwelling adults with or at high risk for symptomatic knee OA. The exposures were stair climbing difficulty and frequency, assessed at baseline using self-report questionnaires. The outcome was all-cause mortality, assessed from baseline through 13 years of follow-up. Kaplan-Meier survival curves and Cox proportional hazards regression were used to investigate the association between stair climbing exposures and all-cause mortality. RESULTS: Three hundred seven (6.81%) and 310 (6.84%) participants in the difficulty and frequency samples, respectively, died during 13 years of follow-up. Those who were limited in any capacity in terms of their stair climbing ability had 54% to 84% greater hazard of all-cause mortality, and those who climbed at least 7 flights of stairs per week had 38% lower hazard of all-cause mortality. CONCLUSION: Adults with or at high risk for knee OA who report difficulty with climbing stairs or who infrequently use stairs are at greater hazard of all-cause mortality. Stair climbing difficulty and frequency are simple to collect and changes may occur early in OA progression, allowing for early intervention. Brief questions about stair climbing behaviors can serve as a functional vital sign within the clinician's toolbox.

Developing a science outreach program and promoting "PhUn" all year with rural K-12 students.

Demonstrating how science relates to human health is an important step for generating K-12 student interest in health-related careers. Science outreach is often performed in urban areas; however, ~20% of K-12 schools are in rural areas. Michigan Technological University is located in Michigan's upper peninsula, which accounts for 30% of the state's land mass but only 3% of the total population. Our goal was to create a science outreach program for reaching K-12 students in our rural region. We assembled a team of undergraduate and graduate students, staff, and faculty to implement science outreach with K-12 students. Specifically, we leveraged existing national and international science outreach events [Physiology Friday, Physiology Understanding (PhUn) Week, National Biomechanics Day] to offer hands-on physiology and biomechanics activities during the year. Between 2016 and 2019, we connected with 31 K-12 schools and impacted 327 elementary (19%), 351 middle school (21%), and 1,018 high school (60%) students (total impact 1,696). Over 90% of the outreach visits took place at the K-12 schools. The hands-on activities were delivered by more than 85 undergraduate and graduate students and 10 faculty. Together, the supportive culture and resources within the department (e.g., outreach coordinator, participation from students and faculty, grant funding) were key to developing the program. We recommend starting with a single outreach event, working as a team, and being flexible with K-12 schools. The program also provided service-learning and professional development opportunities for undergraduate and graduate students and faculty. Our robust science outreach program promoted "PhUn" all year-round with rural K-12 students.

An outside-the-box activity to demonstrate how humans and animals turn.

Developing hands-on activities that engage and excite K-12 students is critical for stimulating interest in science-based careers. We created an activity for high school students that required them to integrate biology and physics concepts to experience how humans and animals maneuver through their environments (i.e., turning). Understanding how turning works is important because it accounts for up to 50% of daily walking steps and is needed for survival when animals elude predators and capture prey. For this activity, student groups used 2 × 4 lumber, wood screws, and a power drill to build an apparatus that, when connected to the body, altered rotational inertia (object's resistance to change in angular motion, I = mass × radius2). Students navigated through a slalom course with the apparatus (increased radius and rotational inertia) and without the apparatus (mass-matched control). Times to complete the course were compared between trials to determine the influence of rotational inertia on turning performance. Students compiled their data, graphed their results, and found that increased rotational inertia decreased turning performance. Results were connected to sports, rehabilitation, and dinosaur evolution. This activity was implemented during local, regional, national, and international outreach events and adapted for use in undergraduate courses as well (total impact, 250 students). At the end of the activity, students were able to 1) describe whether their results supported their hypothesis; 2) explain how radius influences rotational inertia and turning performance; and 3) apply results to real-world examples. Students and teachers appreciated this "outside-the-box" activity with an engineering twist and found it entertaining.

Influence of the Lower Body on Seated Arm Cranking Performance.

During upper-body tasks, use of the lower body is important for minimizing physiological strain and maximizing performance. The lower body has an integral role during standing upper-body tasks, however, it is less clear if it is also important during seated upper-body tasks. We determined the extent to which the lower body influenced seated arm cranking performance. Eleven males performed incremental (40+20 W·3 min-1) and short-duration maximal effort (5 s, 120 rpm) arm cranking trials with and without lower-body restriction. The lower body was restricted by securing the legs to the seat and suspending them off the floor. Upper-body peak oxygen consumption (V̇O2peak) and maximal power were determined. At the end of the incremental protocol, lower-body restriction reduced V̇O2peak by 14±12% (P<0.01) compared to normal arm cranking. At greater submaximal stages (60-100% isotime) heart rate, ventilation, RER, and arm-specific exertion increased to a greater extent (all P<0.05) with lower-body restriction. During short duration maximal arm cranking, lower-body restriction decreased maximal power by 23±9% (P<0.01). Results indicated that lower-body restriction limited aerobic capacity, increased physiological strain during high-intensity submaximal exercise, and compromised maximal power generating capacity. These results imply that use of the lower body is critical when performing seated arm cranking. Our findings have implications for exercise testing, training and rehabilitation.