Effect of Huperzine A on Cognitive Function and Perception of Effort during Exercise: A Randomized Double-Blind Crossover Trial

International Journal of Exercise Science 14(2): 727-741, 2021. Huperzine A has shown the ability to acutely improve cognitive function in certain populations, and therefore is commonly added to pre-workout supplements. However, its effects have not been studied in exercise-trained individuals. OBJECTIVE: We hypothesized that acute consumption of huperzine A would improve cognitive function during exercise, which may be beneficial for exercise performance. METHODS: From January to April, 2018, 15 exercise-trained individuals (11 women [height 166 ± 2 cm, weight 60.5 ± 3.0 kg] and 4 men [height 173 ± 4 cm, weight 82.0 ± 11.0 kg], BMI 23.5 ± 1.4 kg/m2, age 30.4 ± 3.6 years) were studied in a double blind randomized-sequence cross-over study, in which they underwent tests for cognitive function (digit span, verbal/word fluency, and Stroop), neuromuscular performance (sharpened Romberg and dart throwing), and exercise performance (estimated aerobic capacity, hand-grip strength, vertical jump, and push-up) after acute ingestion of huperzine A (200 mcg) or placebo. One week separated the two trials. RESULTS: No measures of cognitive function differed between placebo and huperzine A trials (all p ≥ 0.296). Heart rates (157 ± 4 vs. 158 ± 4 bpm; p = 0.518) and ratings of perceived exertion (13.7 ± 0.56 vs. 13.9 ± 0.61; p = 0.582) did not differ between placebo and huperzine A trials, respectively. Ratings of subjective difficulty post-exercise (0-10 scale) were significantly higher (5.7 ± 0.38 vs. 6.8 ± 0.38; p = 0.002) in the huperzine A trial than the placebo trial. No differences were observed for neuromuscular or exercise performance measures between groups (all p ≥ 0.497). CONCLUSIONS: Huperzine A does not enhance cognitive function during exercise despite it being marketed as a cognitive enhancer. Because of its inability to enhance cognitive function, its inclusion in pre-workout supplements warrants reconsideration. Other more practical and effective strategies should be considered

Effects of dietary acid load on exercise metabolism and anaerobic exercise performance

Dietary acid load, quantified as the potential renal acid load (PRAL) of the diet, affects systemic pH and acid-base regulation. In a previous cross-sectional study, we reported that a low dietary PRAL (i.e. alkaline promoting diet) is associated with higher respiratory exchange ratio (RER) values during maximal exercise. The purpose of the present study was to confirm the previous findings with a short-term dietary intervention study. Additionally, we sought to determine if changes in PRAL affects submaximal exercise RER (as a reflection of substrate utilization) and anaerobic exercise performance. Subjects underwent a graded treadmill exercise test (GXT) to exhaustion and an anaerobic exercise performance test on two occasions, once after following a low-PRAL diet and on a separate occasion, after a high-PRAL diet. The diets were continued as long as needed to achieve an alkaline or acid fasted morning urine pH, respectively, with all being 4-9 days in duration. RER was measured during the GXT with indirect calorimetry. The anaerobic performance test was a running time-to-exhaustion test lasting 1-4 min. Maximal exercise RER was lower in the low-PRAL trial compared to the high-PRAL trial (1.10 ± 0.02 vs. 1.20 ± 0.05, p = 0.037). The low-PRAL diet also resulted in a 21% greater time to exhaustion during anaerobic exercise (2.56 ± 0.36 vs. 2.11 ± 0.31 sec, p = 0.044) and a strong tendency for lower RER values during submaximal exercise at 70% VO(2)max (0.88 ± 0.02 vs. 0.96 ± 0.04, p = 0.060). Contrary to our expectations, a short-term low-PRAL (alkaline promoting) diet resulted in lower RER values during maximal-intensity exercise. However, the low-PRAL diet also increased anaerobic exercise time to exhaustion and appears to have shifted submaximal exercise substrate utilization to favor lipid oxidation and spare carbohydrate, both of which would be considered favorable effects in the context of exercise performance

Spondylarthropathies (including psoriatic arthritis): 244. Validity of Colour Doppler and Spectral Doppler Ultrasound of Sacroilicac Joints Againts Physical Examination as Gold Standard

Background: Sacroiliac joints (SJ) involvement is a distinctive and charasteristic feature of Spondyloarthritis (SpA) and x-ray is the test routinely used to make a diagnosis. However, x-ray reveals late structural damage but cannot detect active inflammation. The objective of this study was to assess the validity of Doppler ultrasound in SJ. Methods: Prospective blinded and controlled study of SJ, in which three populations were compared. We studied 106 consecutive cases, who were divided into three groups: a) 53 patients diagnosed with SpA who had inflammatory lumbar and gluteal pain assessed by a rheumatologist; b) 26 patients diagnosed with SpA who didn't have SJ tenderness and had normal physical examination; c) control group of 27 subjects (healthy subjetcs or with mechanical lumbar pain). All patients included that were diagnosed with SpA met almost the European Spondyloarthropathy Study Group (ESSG) classification criteria. Physical examination of the SJ included: sacral sulcus tenderness, iliac gapping, iliac compression, midline sacral thrust test, Gaenslen's test, and Patrick s test were used as gold standard. Both SJ were examined with Doppler ultrasound (General Electric Logiq 9, Wauwatosa WI, USA) fitted with a 9-14 Mhz lineal probe. The ultrasonographer was blinded to clinical data. Doppler in SJ was assessed as positive when both Doppler colour and resistance index (RI) < 0.75 within the SJ area were present. Statistical analysis was performed estimating sensitivity and specificity against gold standard. The Kappa correlation coefficient was used for reliability study. Results: 106 cases (53 female, 55 male; mean age 36 10 years) were studied. There were no statistical differences between groups related to age or sex. Physical examination of SJ was positive in 38 patients (59 sacroiliac joints). US detected Doppler signal within SJ in 37 patients (58 SJ): 33 of them were symptomatic SpA (52 SJ), one of them were asymptomatic SpA (1 SJ) and one was a healthy control (1 SJ). The accuracy of US when compared to clinical data as gold standard at subject level in the overall group was: sensitivity of 68.6% and specificity of 85.7%, positive predictive value of 70.5% and negative predictive value of 84.5%. A positive likelihood ratio of 4.8, a negative likelihood ratio of 0.36 and a kappa coefficient of 0.55 were achieved. Conclusions: Doppler US of SJ seems to be a valid method to detect active SJ inflammation. Disclosure statement: The authors have declared no conflicts of interes

Examining Teacher-Student Relationships: Moving from Bullying to Caring

This is a qualitative action research study that examines teacher perceptions of behaviors that foster caring teacher-student relationships that motivate students to learn. The purpose of this research was to examine the range of teacher behaviors that either promoting caring teacher-student relationships or which behaviors are disrupting such relationships and could be classified as teacher bullying. The study explores teacher-student relationships in the context of Nel Noddings’ care theory. Eleven teachers from a large suburban middle school in Central Illinois were interviewed and observed. Data that was collected indicated that certain teacher behaviors to promote a caring student-teacher relationship and is indicative of an increased level of student engagement in the classroom and a decreased level of student misbehavior. Three specific areas were identified that need to be addressed in order to create a school climate that fosters positive teacher-student relationships and incorporates the care theory philosophy into each interaction with students and staff

Mechanical loading attenuates loss of bone mass and bone strength induced by immobilization and calcium-deficiency

Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to [email protected], referencing the URI of the item.Includes bibliographical references.Issued also on microfiche from Lange Micrographics.Immobilization and calcium-deficiency have been documented to cause a decrease in strength and bone mineral loss, and exercise is known to strengthen bone. The purpose of this study was to determine the effects of mechanical loading on parameters of bone mass and bone strength in bone subjected to immobilization and calcium-deficiency. Adult female rats were randomly assigned to either a control group (C), immobilized (I) group or an immobilized-loaded (IL) group. The C group had no immobilization and were fed a regular rat chow containing 1.85% calcium. The I group had one hindlimb immobilized by taping and fed a low calcium diet containing 0.01% calcium. The IL group had the same treatment as the immobilized group but had the immobilized limb mechanically loaded by a unique four-point loading machine three times per week. After six weeks of treatment, all animals were sacrificed, both tibia removed and tested for bone mineral density (BMD) by dual energy X-ray absorptiometry, stiffness and ultimate load by three-point bending to failure, cross-sectional moment of inertia, cross-sectional area, and modulus of elasticity. All comparisons were done by one-way ANOVA. When results were found to be significant, Student Newman-Keuls Method post hoc tests when performed. Final results indicate: 1. Six weeks of immobilization by taping and calcium-deficient diet ( I group) decreased cortical BNM by 12%, ultimate load by 19@o and stiffness by 19.77o, when compared to control rats.2. External loading at 34N, 36 cycles @ 2 Hz, three times per week attenuates the decrease in BMD and ultimate load in this model. The IL group mean BMD was only 2.37o lower than the control group mean, and ultimate load was 107o lower than the control group. 3. In this model significant correlations were found between BMD and ultimate load (r=0.754) and BMD and stiffness (r=0.793). This indicates BNM is an effective predictor of bone functional properties in this model

Mechanical loading attenuates loss of bone mass and bone strength induced by immobilization and calcium-deficiency

Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to [email protected], referencing the URI of the item.Includes bibliographical references.Issued also on microfiche from Lange Micrographics.Immobilization and calcium-deficiency have been documented to cause a decrease in strength and bone mineral loss, and exercise is known to strengthen bone. The purpose of this study was to determine the effects of mechanical loading on parameters of bone mass and bone strength in bone subjected to immobilization and calcium-deficiency. Adult female rats were randomly assigned to either a control group (C), immobilized (I) group or an immobilized-loaded (IL) group. The C group had no immobilization and were fed a regular rat chow containing 1.85% calcium. The I group had one hindlimb immobilized by taping and fed a low calcium diet containing 0.01% calcium. The IL group had the same treatment as the immobilized group but had the immobilized limb mechanically loaded by a unique four-point loading machine three times per week. After six weeks of treatment, all animals were sacrificed, both tibia removed and tested for bone mineral density (BMD) by dual energy X-ray absorptiometry, stiffness and ultimate load by three-point bending to failure, cross-sectional moment of inertia, cross-sectional area, and modulus of elasticity. All comparisons were done by one-way ANOVA. When results were found to be significant, Student Newman-Keuls Method post hoc tests when performed. Final results indicate: 1. Six weeks of immobilization by taping and calcium-deficient diet ( I group) decreased cortical BNM by 12%, ultimate load by 19@o and stiffness by 19.77o, when compared to control rats.2. External loading at 34N, 36 cycles @ 2 Hz, three times per week attenuates the decrease in BMD and ultimate load in this model. The IL group mean BMD was only 2.37o lower than the control group mean, and ultimate load was 107o lower than the control group. 3. In this model significant correlations were found between BMD and ultimate load (r=0.754) and BMD and stiffness (r=0.793). This indicates BNM is an effective predictor of bone functional properties in this model

Effects of Dietary Acid Load on Exercise Metabolism and Anaerobic Exercise Performance

Dietary acid load, quantified as the potential renal acid load (PRAL) of the diet, affects systemic pH and acid-base regulation. In a previous cross-sectional study, we reported that a low dietary PRAL (i.e. alkaline promoting diet) is associated with higher respiratory exchange ratio (RER) values during maximal exercise. The purpose of the present study was to confirm the previous findings with a short-term dietary intervention study. Additionally, we sought to determine if changes in PRAL affects submaximal exercise RER (as a reflection of substrate utilization) and anaerobic exercise performance. Subjects underwent a graded treadmill exercise test (GXT) to exhaustion and an anaerobic exercise performance test on two occasions, once after following a low-PRAL diet and on a separate occasion, after a high-PRAL diet. The diets were continued as long as needed to achieve an alkaline or acid fasted morning urine pH, respectively, with all being 4-9 days in duration. RER was measured during the GXT with indirect calorimetry. The anaerobic performance test was a running time-to-exhaustion test lasting 1-4 min. Maximal exercise RER was lower in the low-PRAL trial compared to the high-PRAL trial (1.10 ± 0.02 vs. 1.20 ± 0.05, p = 0.037). The low-PRAL diet also resulted in a 21% greater time to exhaustion during anaerobic exercise (2.56 ± 0.36 vs. 2.11 ± 0.31 sec, p = 0.044) and a strong tendency for lower RER values during submaximal exercise at 70% VO2max (0.88 ± 0.02 vs. 0.96 ± 0.04, p = 0.060). Contrary to our expectations, a short-term low-PRAL (alkaline promoting) diet resulted in lower RER values during maximal-intensity exercise. However, the low-PRAL diet also increased anaerobic exercise time to exhaustion and appears to have shifted submaximal exercise substrate utilization to favor lipid oxidation and spare carbohydrate, both of which would be considered favorable effects in the context of exercise performance