Although the standard methods for determination of CP, RCP, MLSS, and [HHb]BP are different, these indices occur at the same V˙O2p, suggesting that i) they may manifest as a result of similar physiological phenomenon and ii) each provides a valid delineation between tolerable and intolerable constant-power exercise.

The pulmonary O2 uptake (V̇o2p) response to ramp-incremental (RI) exercise increases linearly with work rate (WR) after an early exponential phase, implying that a single time constant (τ) and gain (G) describe the response. However, variability in τ and G of V̇o2p kinetics to different step increments in WR is documented. We hypothesized that the "linear" V̇o2p-WR relationship during RI exercise results from the conflation between WR-dependent changes in τ and G. Nine men performed three or four repeats of RI exercise (30 W/min) and two step-incremental protocols consisting of four 60-W increments beginning from 20 W or 50 W. During testing, breath-by-breath V̇o2p was measured by mass spectrometry and volume turbine. For each individual, the V̇o2p RI response was characterized with exponential functions containing either constant or variable τ and G values. A relationship between τ and G vs. WR was determined from the step-incremental protocols to derive the variable model parameters. τ and G increased from 21 ± 5 to 98 ± 20 s and from 8.7 ± 0.6 to 12.0 ± 1.9 ml·min(-1)·W(-1) for WRs of 20-230 W, respectively, and were best described by a second-order (τ) and a first-order (G) polynomial function of WR (lowest Akaike information criterion score). The sum of squared residuals was not different (P > 0.05) when the V̇o2p RI response was characterized with either the constant or variable models, indicating that they described the response equally well. Results suggest that τ and G increase progressively with WR during RI exercise. Importantly, these relationships may conflate to produce a linear V̇o2p-WR response, emphasizing the influence of metabolic heterogeneity in determining the apparent V̇o2p-WR relationship during RI exercise.

What is the main finding and its importance? 31Here we demonstrate how a first-order system can respond with non-first-order response 32

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Online learning has become an essential part of mainstream higher education. With increasing enrollments in online anatomy courses, a better understanding of effective teaching techniques for the online learning environment is critical. Active learning has previously shown many benefits in face‐to‐face anatomy courses, including increases in student satisfaction. Currently, no research has measured student satisfaction with active learning techniques implemented in an online graduate anatomy course. This study compares student satisfaction across four different active learning techniques (jigsaw, team‐learning module, concept mapping, and question constructing), with consideration of demographics and previous enrollment in anatomy and/or online courses. Survey questions consisted of Likert‐style, multiple‐choice, ranking, and open‐ended questions that asked students to indicate their level of satisfaction with the active learning techniques. One hundred seventy Medical Science master's students completed the online anatomy course and all seven surveys. Results showed that students were significantly more satisfied with question constructing and jigsaw than with concept mapping and team‐learning module. Additionally, historically excluded groups (underrepresented racial minorities) were generally more satisfied with active learning than non‐minority groups. Age, gender, and previous experience with anatomy did not influence the level of satisfaction. However, students with a higher‐grade point average (GPA), those with only a bachelor's degree, and those with no previous online course experience were more satisfied with active learning than students who had a lower GPA, those holding a graduate/professional degree, and those with previous online course experience. Cumulatively, these findings support the beneficial use of active learning in online anatomy courses.

Introduction Sciatic nerve blocks are essential for surgical treatment of various lower limb pathologies. Due to the complexity and variation of anatomical landmarks, ultrasound (US) guided injection of local anesthesia has become common practice. In patients with thicker thigh girth (i.e., obese patients) excess tissue may distort US penetration thereby diminishing efficacy of the nerve block and/or cause severe post‐operative pain. Dye tracing techniques have been used to test the effectiveness of nerve blocks, but there is little research on using massage to manipulate anesthetic spread. Therefore, the aim of this study is to assess the effects of massage to manipulate local anesthesia spread in sciatic nerve blocks. We hypothesize massaging after injection will increase the spread of local anesthesia compared to non‐massage post injection. Methods Forty un‐fixed cadaveric legs were injected with a mixture of methylene blue dye and 2% Lidocaine Hydrochloride. Specimens were divided into non‐massage (control) (n=20) and massage (n=20) groups. Sciatic nerve blocks were performed by a nurse anesthetist using US guidance at the popliteal fossa traveling proximally until the sciatic nerve was identified and the location was tagged. Immediately following, massage group specimens received five repeated proximally directed massages with the US transducer head. Specimens from both groups were then dissected to expose the sciatic nerve. Measurements of the distance traveled from marked site of injection to proximal end of dyed area were measured and compared. Results Spread of local anesthesia in the inferior‐superior direction was significantly higher in the massage group than the control group (p≤0.05). Conclusions Massaging post‐injection caused a greater spread of local anesthesia during sciatic nerve block. Significance Sciatic nerve block techniques often utilize nerve stimulation to identify the sciatic nerve location. This may be due to lack of US penetration through the gluteus maximus muscle. In patients with thicker thigh girth due to subcutaneous fat, imaging visibility may be more difficult as well. Our findings suggest that clinicians may block the sciatic nerve at a more distal location with US guidance and manipulate the anesthesia to the region of interest.

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