Sharon Tsuk | The Zinman College of Physical Education, Wingate Institute (original) (raw)

Papers by Sharon Tsuk

International journal of clinical studies and medical case reports, May 18, 2023

Scientific Journal of Sport and Performance, Nov 29, 2022

Background. The Moringa oleifera (Moringa) nutritional supplement is often used for medicinal pur... more Background. The Moringa oleifera (Moringa) nutritional supplement is often used for medicinal purposes due to its acclaimed healing abilities. Indeed, research indicates that Moringa possesses antioxidant and anti-inflammatory properties, and has the potential of being an ergogenic substance by enhancing energy metabolism. Yet, despite numerous manufacturers producing Moringa-based supplements, little scientific research has been conducted on humans. Aims. The aim of this pilot study was to evaluate the effects of Moringa as an ergogenic aid in improving aerobic and anaerobic exercise performance in healthy young fit subjects. Methods. A randomized, double-blind controlled study was performed to evaluate Moringa supplement compared to placebo. The study included 16 healthy young male and female, age 26.6 ± 3.0 years physical education college students. Participants were evaluated before and after six weeks of intervention of Moringa (310 mg x 2) or placebo capsules. Participants were measured for body composition, resting blood pressure (BP), resting heart rate (HR), graded cardiopulmonary test on a treadmill until reaching maximal oxygen consumption (VO2max) and maximal anaerobic Wingate bicycle test. Results. There were no differences in physiological or physical performances between the two groups before and after the intervention. Conclusions. Despite promising indications of positive effects of Moringa plant on physiological processes, there was no effect on physical activity performance. As such, the administering of Moringa for improving athletic performance should be taken with caution. Further studies should be conducted to examine the effects of the Moringa plant on human performance in other populations.

Heart Failure Reviews, Mar 24, 2022

Journal of Athletic Enhancement, Sep 23, 2021

Molecular Pharmacology, 2004

Kv2.1, the prevalent delayed-rectifier K + channel in neuroendocrine and endocrine cells, was pre... more Kv2.1, the prevalent delayed-rectifier K + channel in neuroendocrine and endocrine cells, was previously suggested by our group to be modulated in islet β-cells by syntaxin 1A (Syx) and SNAP-25 (SNAP). We also demonstrated physical interactions in neuroendocrine cells between Kv2.1, Syx and SNAP-25, characterized their effects on Kv2.1 activation and inactivation in Xenopus oocytes, and suggested that they pertain to the assembly/disassembly of the Syx/SNAP-25 (t-SNARE) complex. In the present work we established the existence of a causal relationship between the physical and the functional interactions of Syx with the Kv2.1 channel, using three different peptides that compete with the channel for binding of Syx when injected into oocytes already coexpressing Syx with Kv2.1 in the plasma membrane. One peptide corresponding to the Syx-binding region on the N-type Ca 2+ channel and two peptides corresponding to Syxbinding regions on the Kv2.1 C-terminus. All peptides reversed the effects of Syx on Kv2.1, suggesting that the hyperpolarizing shifts of the steady-state inactivation and activation of Kv2.1 caused by Syx result from cell-surface protein−protein interactions and point to participation of the C-terminus in such interaction. In line with these findings, the effects of Syx were dissipated by partial deletions of the C-terminus. Furthermore, the t-SNARE complex was shown here to bind to the Kv2.1 C-terminus, and its effects on the inactivation of Kv2.1 were dissipated by partial deletions of the Cterminus. Taken together, these findings suggest that physical interactions of both Syx and the t-SNARE complex with the C-terminus of Kv2.1 are involved in channel regulation.

Journal of Neuroscience, 2007

Kv channels inhibit release indirectly by hyperpolarizing membrane potential, but the significanc... more Kv channels inhibit release indirectly by hyperpolarizing membrane potential, but the significance of Kv channel interaction with the secretory apparatus is not known. The Kv2.1 channel is commonly expressed in the soma and dendrites of neurons, where it could influence the release of neuropeptides and neurotrophins, and in neuroendocrine cells, where it could influence hormone release. Here we show that Kv2.1 channels increase dense-core vesicle (DCV)-mediated release after elevation of cytoplasmic Ca 2ϩ. This facilitation occurs even after disruption of pore function and cannot be explained by changes in membrane potential and cytoplasmic Ca 2ϩ. However, triggering release increases channel binding to syntaxin, a secretory apparatus protein. Disrupting this interaction with competing peptides or by deleting the syntaxin association domain of the channel at the C terminus blocks facilitation of release. Thus, direct association of Kv2.1 with syntaxin promotes exocytosis. The dual functioning of the Kv channel to influence release, through its pore to hyperpolarize the membrane potential and through its C-terminal association with syntaxin to directly facilitate release, reinforces the requirements for repetitive firing for exocytosis of DCVs in neuroendocrine cells and in dendrites.

Journal of Biological Chemistry, 2002

Biology of Reproduction, 2000

Journal of Biological Chemistry, 2009

Journal of Human Kinetics

Photobiomodulation has been shown to improve tissue and cell functions. We evaluated the influenc... more Photobiomodulation has been shown to improve tissue and cell functions. We evaluated the influence of photobiomodulation, using a B-Cure laser, on: 1) maximal performance, and 2) muscle recovery after resistance exercise. Two separate crossover randomized double-blinded placebo-controlled trials were conducted. Sixty healthy physical education students (28 men, 32 women), aged 20-35, were recruited (30 participants for each trial). Participants performed two interventions for each experiment, with real lasers (GaAlAs, 808 nm) on three quadricep locations in parallel (overall treatment energy of ~150J) or sham (placebo) treatment. In the first experiment muscle total work (TW) and peak torque (PT) were measured by an isokinetic dynamometer in five repetitions of knee extension, and in the second experiment muscle recovery was measured after the induction of muscle fatigue by evaluating TW and PT in five repetitions of knee extension. There were no differences between treatments (real...

Advances in Cognitive Psychology

Technology, Haifa, israel cognitive function physical activity cycling strength Acute aerobic exe... more Technology, Haifa, israel cognitive function physical activity cycling strength Acute aerobic exercise was shown to enhance such cognitive functions as executive function (EF) and attention. Acute resistance exercise was also shown to enhance cognitive functions, however, only few studies directly compared these two exercise modalities. The aim of this study was to evaluate the acute effect of a typical moderate intensity resistance exercise session as compared to a typical moderate intensity aerobic session, on executive function and attention. A counterbalanced repeated measures experimental design was applied. Forty physical education students (21 women; 19 men, age = 25.7±2.84 years) were tested before and after three sessions: aerobic, resistance, and control. Each session consisted of 30 minutes of exercise or a rest. Executive function and attention were assessed by components of the computerized Stroop Catch game and Go-NoGo cognitive tests. A two-way ANOVA showed a greater increase in attention scores after the resistance sessions (p < .05) compared to the control condition. Attention scores in the aerobic sessions showed a trend toward improvement but did not reach statistical significance. Scores of EF significantly increased, both after the resistance session and the aerobic session (p < .05), but not after rest in the control condition. Our findings show that an acute session of resistance exercise increased both Attention and EF test scores, while an aerobic exercise session improved only the EF scores.

Advances in Physical Education

Physical education teachers should be able to evaluate exercise intensity objectively as well as ... more Physical education teachers should be able to evaluate exercise intensity objectively as well as subjectively in order to implement the appropriate load during activity sessions. Whereas measuring oxygen uptake or blood lactate level during exercise may be a complicated task in field conditions, monitoring heart rate (HR) values can be a relatively simple procedure when performed outdoors. The aim of this study was to examine the subjective estimation accuracy of HR in different exercises among physical education students. Pre-exercise estimations of HR were collected from 180 students prior to a multi-task activity session. The estimated HR values were then compared with true HR values, which were monitored throughout the session using a portable HR monitor system. A mean significant difference of 13.4% was found between the estimated and actual HRs for all activities. A majority of the students (70%) estimated HR values to be lower than the true values. The most accurate HR estimations were found in extremely easy or in extremely difficult activities, whereas the least accurate estimations were found in moderate-level activities. No significant differences were found in HR estimation accuracy between males and females or between individuals with higher and with lower aerobic fitness. The results indicated that physical education students can estimate their HR responses to a reasonable degree of accuracy, but with most underestimating them compared to the actual values.

International journal of medicinal mushrooms, 2018

Cordyceps sinensis (=Ophiocordyceps sinensis) and Ganoderma lucidum are 2 medicinal mushrooms tha... more Cordyceps sinensis (=Ophiocordyceps sinensis) and Ganoderma lucidum are 2 medicinal mushrooms that have been suggested to have the potential to enhance exercise capacity. We used a commercial supplement combining a traditional Chinese medicine and G. lucidum and tested its effects on human physical, aerobic, and anaerobic capacities. Physical education students (n = 96; 43 women, 53 men; mean ± standard deviation age, 26.3 ± 3.21 years) were randomly divided into 3 groups: low-dose treatment, high-dose treatment, and placebo. Participants received the supplement or the placebo for 28-33 days. Both before and after the intervention, the participants performed a graded maximum oxygen consumption (Vo2max) test on a treadmill and a Wingate anaerobic cycle test (on a different day). The following parameters were measured and recorded during the maximal graded treadmill test: heart rate, oxygen consumption, respiratory exchange ratio, and ventilation. The following parameters were calcula...

International Journal of Medicinal Mushrooms

Ophiocordyceps sinensis (= Cordyceps sinensis) and Ganoderma lucidum are medicinal mushrooms used... more Ophiocordyceps sinensis (= Cordyceps sinensis) and Ganoderma lucidum are medicinal mushrooms used in traditional Chinese medicine. The effects of O. sinensis and G. lucidum on cognitive function have been evaluated through the use of animal models and in vitro studies, which indicated beneficial effects. The purpose of this study was to evaluate the effects of treatment with a commercially available supplement of O. sinensis and G. lucidum on cognitive function in young, healthy human participants. Physical education students (n = 96 [53 men, 43 women]; mean ± standard deviation age, 26.3 ± 3.21 years) were randomly divided into 3 treatment groups: highdose supplement (HD) group, low-dose supplement (LD) group, and a placebo (PL) group. Each group received the treatment, administered by a technician blinded to supplements/placebo, for 30 days. Participants were evaluated for various cognitive functions before and immediately after treatment. Evaluation of cognitive function domains-global cognitive score, memory, executive function, attention, information processing speed, visuospatial ability, verbal function, and motor skills-showed no significant differences between groups. These results indicate that a combination of O. sinensis and G. lucidum supplements for 30 days did not enhance cognitive function domains in young healthy participants.

Brain and Cognition, 2016

Acute exercise appears to facilitate certain aspects of cognitive processing. The possibility tha... more Acute exercise appears to facilitate certain aspects of cognitive processing. The possibility that exercise may lead to more efficient inhibitory processes is of particular interest, owing to the wide range of cognitive and motor functions that inhibition may underlie. The purpose of the present study was to examine the immediate and the delayed effect of acute aerobic exercise on response inhibition, motor planning, and eye-hand coordination in healthy active adults. Forty healthy and active participants (10 females) with a mean age of 51.88±8.46years performed the Go-NoGo test (response inhibition) and the Catch Game (motor planning and eye-hand coordination) before, immediately after, and following a 30-min recovery period in two conditions: a moderate-intensity aerobic session and a control session. In 2-way repeated measures ANOVAs (2 treatments×3 times) followed by contrast comparisons for post hoc analyses, significant pre-post interactions - indicating improvements immediately following exercise but not following the control condition - were observed in the Go-NoGo measures: Accuracy, Reaction Time, and Performance Index, but not in the Catch Game. In the post-follow-up interaction a deterioration was observed in Performance Index, and a trend of deterioration in Accuracy and Reaction Time. The conclusion was that a single session of moderate-intensity aerobic exercise facilitates response inhibition, but not motor planning or eye-hand coordination, in middle-aged healthy active adults. On the other hand, the improvement does not last 30min following a recovery period. Further studies are needed to examine the duration of the inhibitory control benefits and the accumulative effect of a series of acute exercise bouts, as well as to determine the brain networks and/or neurotransmitter systems most affected by the intervention.