Kinesiology Research Works

Permanent URI for this collectionhttp://hdl.handle.net/1903/1635

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    Arterial function in response to a 50 km ultramarathon in recreational athletes
    (Wiley, 2024-06-11) Ranadive, Sushant M.; Weiner, Cynthia M.; Eagan, Lauren E.; Addison, Odessa; Landers-Ramos, Rian Q.; Prior, Steven J.
    This study was performed to determine whether prolonged endurance running results in acute endothelial dysfunction and wave-reflection, as endothelial dysfunction and arterial stiffness are cardiovascular risk factors. Vascular function (conduit artery/macrovascular and resistance artery/microvascular) was assessed in 11 experienced runners (8 males, 3 females) before, during and after a 50 km ultramarathon. Blood pressure (BP), heart rate (HR), wave reflection, augmentation index (AIx) and AIx corrected for HR (AIx75) were taken at all time points—Baseline (BL), following 10, 20, 30 and 40 km, 1 h post-completion (1HP) and 24 h post-completion (24HP). Flow-mediated dilatation (FMD) and inflammatory biomarkers were examined at BL, 1HP and 24HP. Reactive hyperaemia area under the curve (AUC) and shear rate AUC to peak dilatation were lower (∼75%) at 1HP compared with BL (P < 0.001 for both) and reactive hyperaemia was higher at 24HP (∼27%) compared with BL (P = 0.018). Compared to BL, both mean central systolic BP and mean central diastolic BP were 7% and 10% higher, respectively, following 10 km and 6% and 9% higher, respectively, following 20 km, and then decreased by 5% and 8%, respectively, at 24HP (P < 0.05 for all). AIx (%) decreased following 20 km and following 40 km compared with BL (P < 0.05 for both) but increased following 40 km when corrected for HR (AIx75) compared with BL (P = 0.02). Forward wave amplitude significantly increased at 10 km (15%) compared with BL (P = 0.049), whereas backward wave reflection and reflected magnitude were similar at all time points. FMD and baseline diameter remained similar. These data indicate preservation of macrovascular (endothelial) function, but not microvascular function resulting from the 50 km ultramarathon.
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    Acute cycling exercise and hippocampal subfield function and microstructure in healthy older adults
    (Wiley, 2023-08-01) Callow, Daniel D.; Kommula, Yash; Stark, Craig E.L.; Smith, J. Carson
    Aging is associated with deterioration in dentate gyrus (DG) and CA3, both crucial hippocampal subfields for age susceptible memory processes such as mnemonic discrimination (MD). Meanwhile, a single aerobic exercise session alters DG/CA3 function and neural activity in both rats and younger adults and can elicit short-term microstructural alterations in the hippocampus of older adults. However, our understanding of the effects of acute exercise on hippocampal subfield integrity via function and microstructure in older adults is limited. Thus, a within subject-design was employed to determine if 20-min of moderate to vigorous aerobic exercise alters bilateral hippocampal subfield function and microstructure using high-resolution functional magnetic resonance imaging (fMRI) during an MD task (n = 35) and high angular resolution multi-shell diffusion imaging (n = 31), in healthy older adults, compared to seated rest. Following the exercise condition, participants exhibited poorer MD performance, particularly when their perception of effort was higher. Exercise was also related to lower MD-related activity within the DG/CA3 but not CA1 subfield. Finally, after controlling for whole brain gray matter diffusion, exercise was associated with lower neurite density index (NDI) within the DG/CA3. However, exercise-related differences in DG/CA3 activity and NDI were not associated with differences in MD performance. Our results suggest moderate to vigorous aerobic exercise may temporarily inhibit MD performance, and suppress DG/CA3 MD-related activity and NDI, potentially through neuroinflammatory/glial processes. However, additional studies are needed to confirm whether these short-term changes in behavior and hippocampal subfield neurophysiology are beneficial and how they might relate to long-term exercise habits.
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    Arterial stiffness and blood pressure are similar in naturally menstruating and oral contraceptive pill-using women during the higher hormone phases
    (Wiley, 2022-02-24) Eagan, Lauren E.; Chesney, Catalina A.; Mascone, Sara E.; Ranadive, Sushant M.
    New Findings What is the central question of this study? Are there differences in blood pressure, arterial stiffness and indices of pressure waveforms between young oral contraceptive pill-using and naturally menstruating women during lower and higher hormone phases of their cycles? What is the main finding and its importance? Blood pressure, arterial stiffness and indices of pressure waveforms are influenced similarly by exogenous and endogenous hormones. However, lower levels of exogenous hormones moderately increase blood pressure among oral contraceptive pill-using women. Elevations in blood pressure (BP) are understood as having a bidirectional relationship with stiffening of central and peripheral arteries. Arterial stiffness is mitigated by oestrogen, which aides in arterial vasorelaxation. To evaluate whether BP, stiffness, and pressure waveforms were different between young healthy naturally menstruating (non-OCP) and oral contraceptive pill (OCP)-using women, we measured brachial and aortic BPs, carotid-to-femoral pulse wave velocity, carotid β-stiffness, elastic modulus, central augmentation index and augmentation index normalized to a heart rate of 75 bpm, and forward and backward pressure waveforms in 22 women (22 (1) years, OCP: n = 12). To assess phasic differences, women were studied during the early follicular (≤5 days of menstruation onset) and early luteal (4 (2) days post-ovulation) phases of non-OCP and compared to the placebo pill (≤5 days of onset) and active pill (≤5 days of highest-dose active pill) phases of OCP. During the lower hormone phases, OCP users had significantly higher brachial systolic blood pressure (SBP) (119.3 (8.3) vs. 110.2 (8.3) mmHg, P = 0.02) and aortic SBP (104.10 (7.44) vs. 96.80 (6.39) mmHg, P = 0.03) as compared to non-OCP users; however, during the higher hormone phases, there were no differences in measures of brachial or aortic BP, arterial stiffness, or indices of BP waveforms between OCP and non-OCP users (P ≥ 0.05). In conclusion, exogenous and endogenous hormones have similar influences on BP and arterial stiffness; however, lower levels of exogenous hormones augment both central and peripheral BPs.
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    Race and sex differences in ROS production and SOD activity in HUVECs
    (PLoS, 2023-10-04) Mascone, Sara E.; Kim, Katherine I.; Evans, William S.; Prior, Steven J.; Cook, Marc D.; Ranadive, Sushant M.
    Black individuals and men are predisposed to an earlier onset and higher prevalence of hypertension, compared with White individuals and women, respectively. Therefore, the influence of race and sex on reactive oxygen species (ROS) production and superoxide dismutase (SOD) activity following induced inflammation was evaluated in female and male human umbilical vein endothelial cells (HUVECs) from Black and White individuals. It was hypothesized that HUVECs from Black individuals and male HUVECs would exhibit greater ROS production and impaired SOD activity. Inflammation was induced in HUVEC cell lines (n = 4/group) using tumor necrosis factor-alpha (TNF-α, 50ng/ml). There were no between group differences in ROS production or SOD activity in HUVECs from Black and White individuals, and HUVECs from Black individuals exhibited similar SOD activity at 24hr compared with 4hr of TNF-α treatment (p>0.05). However, HUVECs from White individuals exhibited significantly greater SOD Activity (p<0.05) at 24hr as compared to 4hr in the control condition but not with TNF-α treatment (p>0.05). Female HUVECs exhibited significantly lower ROS production than male HUVECs in the control condition and following TNF-α induced inflammation (p<0.05). Only female HUVECs exhibited significant increases in SOD activity with increased exposure time to TNF-α induced inflammation (p<0.05). HUVECs from White individuals alone exhibit blunted SOD activity when comparing control and TNF-α conditions. Further, compared to female HUVECs, male HUVECs exhibit a pro-inflammatory state.
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    Environments, Behaviors, and Inequalities: Reflecting on the Impacts of the Influenza and Coronavirus Pandemics in the United States
    (MDPI, 2020-06-22) Roberts, Jennifer D.; Tehrani, Shadi O.
    In the past century, dramatic shifts in demographics, globalization and urbanization have facilitated the rapid spread and transmission of infectious diseases across continents and countries. In a matter of weeks, the 2019 coronavirus pandemic devastated communities worldwide and reinforced the human perception of frailty and mortality. Even though the end of this pandemic story has yet to unfold, there is one parallel that is undeniable when a comparison is drawn between the 2019 coronavirus and the 1918 influenza pandemics. The public health response to disease outbreaks has remained nearly unchanged in the last 101 years. Furthermore, the role of environments and human behaviors on the effect and response to the coronavirus pandemic has brought to light many of the historic and contemporaneous inequalities and injustices that plague the United States. Through a reflection of these pandemic experiences, the American burden of disparity and disproportionality on morbidity, mortality and overall social determinants of health has been examined. Finally, a reimagination of a post-coronavirus existence has also been presented along with a discussion of possible solutions and considerations for moving forward to a new and better normal.
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    Cardiorespiratory Fitness as a Moderator of Sleep-Related Associations with Hippocampal Volume and Cognition
    (MDPI, 2022-10-07) Alfini, Alfonso J.; Won, Junyeon; Weiss, Lauren R.; Nyhuis, Casandra C.; Zipunnikov, Vadim; Spira, Adam P.; Liu-Ambrose, Teresa; Shackman, Alexander J.; Smith, J. Carson
    The objective of this study was to understand the associations of sleep and cardiorespiratory fitness with hippocampal volume and global cognition among older adults (n = 30, age = 65.8 years, female = 73.3%). Wrist actigraphy provided objective measures of nighttime sleep including sleep duration, average wake bout length (WBL; sleep disturbance), and wake-to-sleep transition probability (WTSP; sleep consolidation). Cardiorespiratory fitness was quantified via cycle exercise using a modified heart rate recovery approach. Magnetic resonance imaging was used to determine hippocampal volume and the Mini-Mental State Examination was used to assess global cognition. Fitness moderated associations of sleep with hippocampal volume and cognitive performance, whereby the association of WBL—an index of poor sleep—with hippocampal atrophy was stronger among less-fit individuals, and the association of sleep duration with cognitive performance was stronger among more-fit individuals. Across the fitness levels, a longer WBL was associated with lower cognitive performance, and a higher WTSP—an index of more consolidated sleep—was associated with greater hippocampal volume. Sleep and fitness were unrelated to the volume of an amygdala control region, suggesting a degree of neuroanatomical specificity. In conclusion, higher cardiorespiratory fitness may attenuate sleep disturbance-related hippocampal atrophy and magnify the cognitive benefits of good sleep. Prospective studies are needed to confirm these findings.
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    Emotional processing and positive affect after acute exercise in healthy older adults
    (Wiley, 2023-06-12) Kommula, Yash; Purcell, Jeremy J.; Callow, Daniel D.; Won, Junyeon; Pena, Gabriel S.; Smith, J. Carson
    The well-elucidated improvement of mood immediately after exercise in older adults presumably involves adaptations in emotion-processing brain networks. However, little is known about effects of acute exercise on appetitive and aversive emotion-related network recruitment in older adults. The purpose of this study was to determine the effect of acute exercise, compared to a seated rest control condition, on pleasant and unpleasant emotion-related regional activation in healthy older adults. Functional MRI data were acquired from 32 active older adults during blocked presentations of pleasant, neutral and unpleasant images from the International Affective Pictures System. fMRI data were collected after participants completed 30 min of moderate to vigorous intensity cycling or seated rest, performed in a counterbalanced order across separate days in a within-subject design. The findings suggest three ways that emotional processing in the brain may be different immediately after exercise (relative to immediately after rest): First, reduced demands on emotional regulation during pleasant emotional processing as indicated by lower precuneus activation for pleasant stimuli; second, reduced processing of negative emotional stimuli in visual association areas as indicated by lower activation for unpleasant stimuli in the bilateral fusiform and ITG; third, an increased recruitment in activation associated with regulating/inhibiting unpleasant emotional processing in the bilateral medial superior frontal gyrus (dorsomedial prefrontal cortex), angular gyri, supramarginal gyri, left cerebellar crus I/II and a portion of right dorsolateral prefrontal cortex. Overall, these findings support that acute exercise in active older adults alters activation in key emotional processing and regulating brain regions.
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    Effects of acute aerobic exercise on mnemonic discrimination performance in older adults
    (Cambridge University Press, 2022-08-15) Callow, Daniel D.; Pena, Gabriel S.; Stark, Craig E. L.; Smith, J. Carson
    Objectives:Ample evidence suggests exercise is beneficial for hippocampal function. Furthermore, a single session of aerobic exercise provides immediate benefits to mnemonic discrimination performance, a highly hippocampal-specific memory process, in healthy younger adults. However, it is unknown if a single session of aerobic exercise alters mnemonic discrimination in older adults, who generally exhibit greater hippocampal deterioration and deficits in mnemonic discrimination performance. Methods: We conducted a within subject acute exercise study in 30 cognitively healthy and physically active older adults who underwent baseline testing and then completed two experimental visits in which they performed a mnemonic discrimination task before and after either 30 min of cycling exercise or 30 min of seated rest. Linear mixed-effects analyses were conducted in which condition order and age were controlled, time (pre vs. post) and condition (exercise vs. rest) were modeled as fixed effects, and subject as a random effect. Results: No significant time by condition interaction effect was found for object recognition (p = .254, η2 =.01), while a significant reduction in interference was found for mnemonic discrimination performance following the exercise condition (p = .012, η2 =.07). A post-intervention only analysis indicated that there was no difference between condition for object recognition (p = .186, η2 =.06), but that participants had better mnemonic discrimination performance (p < .001, η2 =.22) following the exercise. Conclusions: Our results suggest a single session of moderate-intensity aerobic exercise may reduce interference and elicit better mnemonic discrimination performance in healthy older adults, suggesting benefits for hippocampal-specific memory function.
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    Unveiling the neuromechanical mechanisms underlying the synergistic interactions in human sensorimotor system
    (Springer Nature, 2021-01-08) Honarvar, S.; Kim, C.; Diaz-Mercado, Y.; Koh, K.; Kwon, H. J.; Kiemel, T.; Caminita, M.; Hahn, J. O.; Shim, J. K.
    Motor synergies are neural organizations of a set of redundant motor effectors that interact with one another to compensate for each other’s error and ensure the stabilization of a performance variable. Recent studies have demonstrated that central nervous system synergistically coordinates its numerous motor effectors through Bayesian multi-sensory integration. Deficiency in sensory synergy weakens the synergistic interaction between the motor effectors. Here, we scrutinize the neuromechanical mechanism underlying this phenomenon through spectral analysis and modeling. We validate our model-generated results using experimental data reported in the literature collected from participants performing a finger force production task with and without tactile feedback (manipulated through injection of anesthetic in fingers). Spectral analysis reveals that the error compensation feature of synergies occurs only at low frequencies. Modeling suggests that the neurophysiological structures involving short-latency back-coupling loops similar to the well-known Renshaw cells explain the deterioration of synergy due to sensory deprivation.
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    Sensory-to-Motor Overflow: Cooling Foot Soles Impedes Squat Jump Performance
    (Frontiers, 2020-10-09) Caminita, Mia; Garcia, Gina L.; Kwon, Hyun Joon; Miller, Ross H.; Shim, Jae Kun
    Evidence from recent studies on animals and humans suggest that neural overflow from the primary sensory cortex (S1) to the primary motor cortex (M1) may play a critical role in motor control. However, it is unclear if whole-body maximal motor tasks are also governed by this mechanism. Maximum vertical squat jumps were performed by 15 young adults before cooling, then immediately following a 15-min cooling period using an ice-water bath for the foot soles, and finally immediately following a 15-min period of natural recovery from cooling. Jump heights were, on average, 3.1 cm lower immediately following cooling compared to before cooling (p = 3.39 × 10−8) and 1.9 cm lower following natural recovery from cooling (p = 0.00124). The average vertical ground reaction force (vGRF) was also lower by 78.2 N in the condition immediately following cooling compared to before cooling (p = 8.1 × 10−5) and 56.7N lower following natural recovery from cooling (p = 0.0043). The current study supports the S1-to-M1 overflow mechanism in a whole-body dynamic jump.