Implementation of Supplemental Instruction for Physical Therapist Students in an Exercise Physiology Course

An ongoing challenge for faculty is to determine effective and efficient mechanisms for assisting students to achieve academic success. Supplemental Instruction (SI), a form of peer tutoring, has been defined as a peer-led academic assistance program that targets difficult courses and is offered to students enrolled in those courses. Based on student feedback that exercise physiology is difficult, the authors chose this course in the Doctor of Physical Therapy (DPT) curriculum for this post-only pilot study. SI was offered over a three-year period to physical therapist students enrolled in an exercise physiology course. The purposes of this study were to 1) determine the perceived benefits of SI by students who attended at least one session, 2) identify reasons students never attended SI or started attending SI and then stopped, 3) identify the degree of student satisfaction with SI, and 4) identify students’ willingness to recommend SI for exercise physiology or other DPT courses. An 18-item written questionnaire was the assessment method. A total of 203 students participated over the three-year period. Frequency distributions and percentages were calculated for each of the multiple choice questionnaire items to determine results of students’ perceptions of SI. Students’ perceived benefits included 1) improved academic performance, 2) improved confidence, 3) increased contact with other students, 4) improved understanding of the material, 5) improved motivation to learn, and 6) improved understanding of instructor expectations. Frequently cited reasons for never attending were conflicts with other courses and/or work schedule, and not perceiving the service as needed. Students cited lack of time to attend sessions and alternative study methods as frequent reasons for attending SI and then stopping. In each of the three years, at least 85% of the students who attended at least one SI session were satisfied. The percentage of students who would recommend SI for exercise physiology or other DPT courses was consistently ≥ 70%. Given the positive outcomes of this three-year implementation of SI in an entry-level physical therapy curriculum, other colleges and universities may wish to consider implementation of an SI program for health professions’ courses

Exercise improves phosphatidylinositol-3,4,5-trisphosphate responsiveness of atypical protein kinase C and interacts with insulin signalling to peptide elongation in human skeletal muscle

We investigated if acute endurance-type exercise interacts with insulin-stimulated activation of atypical protein kinase C (aPKC) and insulin signalling to peptide chain elongation in human skeletal muscle. Four hours after acute one-legged exercise, insulin-induced glucose uptake was ∼80% higher (N = 12, P < 0.05) in previously exercised muscle, measured during a euglycaemic–hyperinsulinaemic clamp (100 μU ml−1). Insulin increased (P < 0.05) both insulin receptor substrate (IRS)-1 and IRS-2 associated phosphatidylinositol (PI)-3 kinase activity and led to increased (P < 0.001) phosphorylation of Akt on Ser473 and Thr308 in skeletal muscle. Interestingly, in response to prior exercise IRS-2-associated PI-3 kinase activity was higher (P < 0.05) both at basal and during insulin stimulation. This coincided with correspondingly altered phosphorylation of the extracellular-regulated protein kinase 1/2 (ERK 1/2), p70S6 kinase (P70S6K), eukaryotic elongation factor 2 (eEF2) kinase and eEF2. aPKC was similarly activated by insulin in rested and exercised muscle, without detectable changes in aPKC Thr410 phosphorylation. However, when adding phosphatidylinositol-3,4,5-triphosphate (PIP3), the signalling product of PI-3 kinase, to basal muscle homogenates, aPKC was more potently activated (P = 0.01) in previously exercised muscle. Collectively, this study shows that endurance-type exercise interacts with insulin signalling to peptide chain elongation. Although protein turnover was not evaluated, this suggests that capacity for protein synthesis after acute endurance-type exercise may be improved. Furthermore, endurance exercise increased the responsiveness of aPKC to PIP3 providing a possible link to improved insulin-stimulated glucose uptake after exercise

Dose-response effects of dietary protein on muscle protein synthesis during recovery from endurance exercise in young men: a double-blind randomized trial

Background Protein ingestion increases skeletal muscle protein synthesis rates during recovery from endurance exercise. Objectives We aimed to determine the effect of graded doses of dietary protein co-ingested with carbohydrate on whole-body protein metabolism, and skeletal muscle myofibrillar (MyoPS) and mitochondrial (MitoPS) protein synthesis rates during recovery from endurance exercise. Methods In a randomized, double-blind, parallel-group design, 48 healthy, young, endurance-trained men (mean ± SEM age: 27 ± 1 y) received a primed continuous infusion of L-[ring-2H5]-phenylalanine, L-[ring-3,5-2H2]-tyrosine, and L-[1-13C]-leucine and ingested 45 g carbohydrate with either 0 (0 g PRO), 15 (15 g PRO), 30 (30 g PRO), or 45 (45 g PRO) g intrinsically L-[1-13C]-phenylalanine and L-[1-13C]-leucine labeled milk protein after endurance exercise. Blood and muscle biopsy samples were collected over 360 min of postexercise recovery to assess whole-body protein metabolism and both MyoPS and MitoPS rates. Results Protein intake resulted in ∼70%–74% of the ingested protein-derived phenylalanine appearing in the circulation. Whole-body net protein balance increased dose-dependently after ingestion of 0, 15, 30, or 45 g protein (mean ± SEM: −0.31± 0.16, 5.08 ± 0.21, 10.04 ± 0.30, and 13.49 ± 0.55 μmol phenylalanine · kg−1 · h−1, respectively; P < 0.001). 30 g PRO stimulated a ∼46% increase in MyoPS rates (%/h) compared with 0 g PRO and was sufficient to maximize MyoPS rates after endurance exercise. MitoPS rates were not increased after protein ingestion; however, incorporation of dietary protein–derived L-[1-13C]-phenylalanine into de novo mitochondrial protein increased dose-dependently after ingestion of 15, 30, and 45 g protein at 360 min postexercise (0.018 ± 0.002, 0.034 ± 0.002, and 0.046 ± 0.003 mole percentage excess, respectively; P < 0.001). Conclusions Protein ingested after endurance exercise is efficiently digested and absorbed into the circulation. Whole-body net protein balance and dietary protein–derived amino acid incorporation into mitochondrial protein respond to increasing protein intake in a dose-dependent manner. Ingestion of 30 g protein is sufficient to maximize MyoPS rates during recovery from a single bout of endurance exercise. This trial was registered at trialregister.nl as NTR5111