Micah Zuhl

Dr. Micah Zuhl


Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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15 January 2014 in Journal of Applied Physiology
Verified
Journal Article
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MZMicah Zuhl
Micah Zuhl
Rosie LanphereRosie Lanphere
Rosie Lanphere
LKLen Kravitz
Len Kravitz
CMChristine M. Mermier
Christine M. Mermier
SSSuzanne Schneider
Suzanne Schneider
PMPope L. Moseley
Pope L. Moseley
The objectives of this study are threefold: 1) to assess whether 7 days of oral glutamine (GLN) supplementation reduces exercise-induced intestinal permeability; 2) whether supplementation prevents the proinflammatory response; and 3) whether these changes are associated with upregulation of the heat shock response. On separate occasions, eight human subjects participated in baseline testing and in GLN and placebo (PLA) supplementation trials, followed by a 60-min treadmill run. Intestinal permeability was higher in the PLA trial compared with baseline and GLN trials (0.0604 ± 0.047 vs. 0.0218 ± 0.008 and 0.0272 ± 0.007, respectively; P < 0.05). IκBα expression in peripheral blood mononuclear cells was higher 240 min after exercise in the GLN trial compared with the PLA trial (1.411 ± 0.523 vs. 0.9839 ± 0.343, respectively; P < 0.05). In vitro using the intestinal epithelial cell line Caco-2, we measured effects of GLN supplementation (0, 4, and 6 mM) on heat-induced (37° or 41.8°C) heat shock protein 70 (HSP70), heat shock factor-1 (HSF-1), and occludin expression. HSF-1 and HSP70 levels increased in 6 mM supplementation at 41°C compared with 0 mM at 41°C (1.785 ± 0.495 vs. 0.6681 ± 0.290, and 1.973 ± 0.325 vs. 1.133 ± 0.129, respectively; P < 0.05). Occludin levels increased after 4 mM supplementation at 41°C and 6 mM at 41°C compared with 0 mM at 41°C (1.236 ± 0.219 and 1.849 ± 0.564 vs. 0.7434 ± 0.027, respectively; P < 0.001). GLN supplementation prevented exercise-induced permeability, possibly through HSF-1 activation.

1 January 2015 in Cell Stress and Chaperones
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Journal Article
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MZMicah Zuhl
Micah Zuhl
KDKarol Dokladny
Karol Dokladny
CMChristine Mermier
Christine Mermier
SSSuzanne Schneider
Suzanne Schneider
RSRoy Salgado
Roy Salgado
PMPope Moseley
Pope Moseley
Chronic glutamine supplementation reduces exercise-induced intestinal permeability and inhibits the NF-κB pro-inflammatory pathway in human peripheral blood mononuclear cells. These effects were correlated with activation of HSP70. The purpose of this paper is to test if an acute dose of oral glutamine prior to exercise reduces intestinal permeability along with activation of the heat shock response leading to inhibition of pro-inflammatory markers. Physically active subjects (N = 7) completed baseline and exercise intestinal permeability tests, determined by the percent ratio of urinary lactulose (5 g) to rhamnose (2 g). Exercise included two 60-min treadmill runs at 70 % of VO2max at 30 °C after ingestion of glutamine (Gln) or placebo (Pla). Plasma levels of endotoxin and TNF-α, along with peripheral blood mononuclear cell (PBMC) protein expression of HSP70 and IκBα, were measured pre- and post-exercise and 2 and 4 h post-exercise. Permeability increased in the Pla trial compared to that at rest (0.06 ± 0.01 vs. 0.02 ± 0.018) and did not increase in the Gln trial. Plasma endotoxin was lower at the 4-h time point in the Gln vs. 4 h in the Pla (6.715 ± 0.046 pg/ml vs. 7.952 ± 1.11 pg/ml). TNF-α was lower 4 h post-exercise in the Gln vs. Pla (1.64 ± 0.09 pg/ml vs. 1.87 ± 0.12 pg/ml). PBMC expression of IkBα was higher 4 h post-exercise in the Gln vs. 4 h in the Pla (1.29 ± 0.43 vs. 0.8892 ± 0.040). HSP70 was higher pre-exercise and 2 h post-exercise in the Gln vs. Pla (1.35 ± 0.21 vs. 1.000 ± 0.000 and 1.65 ± 0.21 vs. 1.27 ± 0.40). Acute oral glutamine supplementation prevents an exercise-induced rise in intestinal permeability and suppresses NF-κB activation in peripheral blood mononuclear cells.

26 July 2019 in Behavioral Sciences
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Terence MoriartyTerence Moriarty
Terence Moriarty
KBKelsey Bourbeau
Kelsey Bourbeau
BBBryanne Bellovary
Bryanne Bellovary
MZMicah Zuhl
Micah Zuhl
Activation changes in the prefrontal cortex (PFC) regions have been linked to acute exercise-induced improvements in cognitive performance. The type of exercise performed may influence PFC activation, and further impact cognitive function. The present study aimed to compare PFC activation during cognitive testing after moderate-intensity, high intensity, and yoga exercises, and to determine if PFC activation is linked to cognitive performance. Eight subjects (four male and four female), aged 35 ± 5 completed a control, high intensity, moderate intensity, and yoga exercises followed by administration of a cognitive task (NIH Toolbox Fluid Cognition). Left and right PFC activation (LPFC and RPFC, respectively) were evaluated by measuring hemoglobin difference (Hbdiff) changes during post-exercise cognitive assessment using functional near infrared spectroscopy (fNIRS). Activation during the cognitive test was higher in the LPFC after moderate intensity exercise compared to control, high intensity, and yoga (5.30 ± 6.65 vs. 2.26 ± 2.40, 2.50 ± 1.48, 2.41 ± 2.36 μM, p < 0.05, respectively). A negative relationship was detected between LPFC and processing speed after exercise. PFC activation did not align with cognitive performance. However, acute exercise, regardless of type, appeared to alter neural processing. Specifically, less PFC activation was required for a given neural output after exercise.

14 July 2020 in Behavioral Sciences
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KBKelsey Bourbeau
Kelsey Bourbeau
Terence MoriartyTerence Moriarty
Terence Moriarty
AAAkeisha Ayanniyi
Akeisha Ayanniyi
MZMicah Zuhl
Micah Zuhl
Behavioral therapy (BT) and exercise are efficacious treatments for depression and anxiety when employed separately. The combination of BT and exercise (BT+Ex) may augment improvements but the combined effect of these therapies is not fully elucidated. The purpose of this meta-analysis was to determine if BT+Ex yielded a significant reduction in depression and anxiety symptoms compared to BT alone (BT). Randomized controlled studies published prior to September 2019 were searched among several databases (PUBMED, MEDLINE, PsychArticle, and Cochrane Central Register of Clinical Trials). Studies that measured depression and anxiety symptoms following BT+Ex vs. BT were extracted and analyzed. The effect of these therapies on depression and anxiety were analyzed. Subgroup analyses were performed to evaluate the effect of exercise intensity (moderate and high), exercise type (aerobic and combined exercise), and baseline levels of depression. The moderating effects of gender, age, and treatment duration were performed. Data were extracted from 18 studies (1686 participants, mean age = 47 years, 65% female). There was a significant effect of BT+Ex on symptoms of depression. The effect of BT+Ex was significant for moderate intensity exercise and elevated baseline levels of depression. Age moderated the effect for depression. There was a significant effect of BT+Ex on depressive symptoms in humans. Exercise intensity and elevated depressive symptoms may play a role in the effect of exercise.

Verified
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MMMegan Mytinger
Megan Mytinger
RNRachael Nelson
Rachael Nelson
MZMicah Zuhl
Micah Zuhl
Aerobic exercise is a core component of cardiac rehabilitation (CR). Leading organizations recommend that the exercise prescriptions should be based on a symptom limited baseline graded exercise test (GXT). However, recent evidence suggests that only ~30% of CR clinics perform baseline GXTs. Consequently, exercise prescriptions including exercise progression in CR are not following standard exercise prescription guidelines. Therefore, the purpose of this review is to provide clinicians with evidence-based techniques for prescribing exercise in the absence of a baseline GXT. Intensity indicators (e.g., heart rate, perceived exertion) are reviewed, along with special exercise considerations for various disease states (e.g., heart failure, peripheral artery disease, and coronary artery disease). Baseline exercise testing remains the gold standard approach for prescribing exercise among heart disease patients, however, clinicians must be prepared to safely develop and monitor patients when a baseline GXT is not performed.

9 July 2021 in Frontiers in Sports and Active Living
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Journal Article
Open access
KCKathryn E. Coakley
Kathryn E. Coakley
DLDavid T. Lardier
David T. Lardier
KHKelley R. Holladay
Kelley R. Holladay
FAFabiano T. Amorim
Fabiano T. Amorim
MZMicah Zuhl
Micah Zuhl
Background: The coronavirus disease 2019 (COVID-19) pandemic placed social, travel, school access, and learning restrictions on University students. Excessive restriction measures have been shown to have negative impacts on mental health. Physical activity preserves mental health, and may be useful during quarantines.Purpose: Explore physical activity and sedentary behavior and associations with depression and anxiety symptoms among University students during COVID-19 restrictions in the Fall 2020 semester.Methods: Six hundred and ninety-seven undergraduates (18–25 years) from a U.S. public University completed a cross-sectional survey in fall 2020. The survey included demographic questions, the Generalized Anxiety Disorder Scale 7 (GAD-7), the Patient Health Questionnaire 9 (PHQ-9), and questions about meeting moderate to vigorous physical activity (MVPA) recommendations and sedentary behavior.Results: Forty-nine percent did not meet MVPA guidelines. Patient Health Questionnaire 9 (p = 0.002) and GAD-7 (p = 0.024) scores were higher among those who did not achieve MVPA. Sitting time (h/day) was a significant associated with depression (B = 0.29 (0.06), p < 0.05, 95% CI = 0.18, 0.41) and anxiety (B = 0.24 (0.05), p < 0.05, 95% CI = 0.13, 0.34) severity.Conclusion: Physical activity was associated with mental health among University students during COVID-19 lockdowns.