Physiological and perceptual responses to acute arm cranking with blood flow restriction.

INTRODUCTION: Lower-body aerobic exercise with blood flow restriction (BFR) offers a unique approach for stimulating improvements in muscular function and aerobic capacity. While there are more than 40 reports documenting acute and chronic responses to lower-body aerobic exercise with BFR, responses to upper-body aerobic exercise with BFR are not clearly established. PURPOSE: We evaluated acute physiological and perceptual responses to arm cranking with and without BFR. METHODS: Participants (N = 10) completed 4 arm cranking (6 × 2 min exercise, 1 min recovery) conditions: low-intensity at 40%VO2peak (LI), low-intensity at 40%VO2peak with BFR at 50% of arterial occlusion pressure (BFR50), low-intensity at 40%VO2peak with BFR at 70% of arterial occlusion pressure (BFR70), and high-intensity at 80%VO2peak (HI) while tissue oxygenation, cardiorespiratory, and perceptual responses were assessed. RESULTS: During exercise, tissue saturation for BFR50 (54 ± 6%), BFR70 (55 ± 6%), and HI (54 ± 8%) decreased compared to LI (61 ± 5%, all P < 0.01) and changes in deoxyhemoglobin for BFR50 (11 ± 4), BFR70 (15 ± 6), and HI (16 ± 10) increased compared to LI (4 ± 2, all P < 0.01). During recovery intervals, tissue saturation for BFR50 and BFR70 decreased further and deoxyhemoglobin for BFR50 and BFR70 increased further (all P < 0.04). Heart rate for BFR70 and HI increased by 9 ± 9 and 50 ± 15b/min, respectively, compared to LI (both P < 0.02). BFR50 (8 ± 2, 1.0 ± 1.0) and BFR70 (10 ± 2, 2.1 ± 1.4) elicited greater arm-specific perceived exertion (6-20 scale) and pain (0-10 scale) compared to LI (7 ± 1, 0.2 ± 0.5, all P < 0.05) and pain for BFR70 did not differ from HI (1.7 ± 1.9). CONCLUSION: Arm cranking with BFR decreased tissue saturation and increased deoxyhemoglobin without causing excessive cardiorespiratory strain and pain.

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.