Search results for "Heart"

Trajectories of Blood Pressure Elevation Preceding Hypertension Onset: An Analysis of the Framingham Heart Study Original Cohort

2018

Importance Given that hypertension remains a leading risk factor for chronic disease globally, there are substantial ongoing efforts to define the optimal range of blood pressure (BP). Objective To identify a common threshold level above which BP rise tends to accelerate in progression toward hypertension. Design, Setting, and Participants This longitudinal, community-based epidemiological cohort study of adults enrolled in Framingham, Massachusetts, included 1252 participants (mean [SD] age, 35.3 [2.7] years) from the Framingham Original Cohort, of whom 790 (63.1%) were women. Each participant contributed up to 28 serial examinations of standardized resting BP measurements between 1948 and…

Individual Endurance Training Prescription with Heart Rate Variability

2016

Introduction: Measures of HR variability (HRV) have shown potential to be of use in training prescription. Purpose: The aim of this study was to investigate the effectiveness of using HRV in endurance training prescription. Methods: Forty recreational endurance runners were divided into the HRV-guided experimental training group (EXP) and traditional predefined training group (TRAD). After a 4-wk preparation training period, TRAD trained according to a predefined training program including two to three moderate- (MOD) and high-intensity training (HIT) sessions per week during an 8-wk intensive training period. The timing of MOD and HIT sessions in EXP was based on HRV, measured every mornin…

Effects of β-adrenergic blockade on EMG signal characteristics during progressive exercise

1984

Excitability regulation in the dorsomedial prefrontal cortex during sustained instructed fear responses: a TMS-EEG study

2018

AbstractThreat detection is essential for protecting individuals from adverse situations, in which a network of amygdala, limbic regions and dorsomedial prefrontal cortex (dmPFC) regions are involved in fear processing. Excitability regulation in the dmPFC might be crucial for fear processing, while abnormal patterns could lead to mental illness. Notwithstanding, non-invasive paradigms to measure excitability regulation during fear processing in humans are missing. To address this challenge we adapted an approach for excitability characterization, combining electroencephalography (EEG) and transcranial magnetic stimulation (TMS) over the dmPFC during an instructed fear paradigm, to dynamica…

Preferential patterns of myocardial iron overload by multislice multiecho T2* CMR in thalassemia major patients.

2010

T*(2) multislice multiecho cardiac MR allows quantification of the segmental distribution of myocardial iron overload. This study aimed to determine if there were preferential patterns of myocardial iron overload in thalassemia major. Five hundred twenty-three thalassemia major patients underwent cardiac MR. Three short-axis views of the left ventricle were acquired and analyzed using a 16-segment standardized model. The T*(2) value on each segment was calculated, as well as the global value. Four main circumferential regions (anterior, septal, inferior, and lateral) were defined. Significant segmental variability was found in the 229 patients with significant myocardial iron overload (glob…

Arousal/Stress Effects of “Overwatch” eSports Game Competition in Collegiate Gamers

2022

Kraemer, WJ, Caldwell, LK, Post, EM, Beeler, MK, Emerson, A, Volek, JS, Maresh, CM, Fogt, JS, Fogt, N, Häkkinen, K, Newton, RU, Lopez, P, Sanchez, BN, and Onate, JA. Arousal/stress effects of “Overwatch” eSports game competition in collegiate gamers. J Strength Cond Res XX(X): 000–000, 2022—To date, no physical response data are available for one of the most popular eSport games, Overwatch. The purpose of this investigation was to describe the stress signaling associated with competitive Overwatch play and to understand how acute hormonal responses may affect performance. Thirty-two male college-aged gamers (age: 21.3 ± 2.7 years; estimated time played per week: 18 ± 15 hours) completed the…

Mentalizing eye contact with a face on a video : Gaze direction does not influence autonomic arousal

2018

Recent research has revealed enhanced autonomic and subjective responses to eye contact only when perceiving another live person. However, these enhanced responses to eye contact are abolished if the viewer believes that the other person is not able to look back at the viewer. We purported to investigate whether this "genuine" eye contact effect can be reproduced with pre-recorded videos of stimulus persons. Autonomic responses, gaze behavior, and subjective self-assessments were measured while participants viewed pre-recorded video persons with direct or averted gaze, imagined that the video person was real, and mentalized that the person could see them or not. Pre-recorded videos did not …

Cardiorespiratory Changes During Prolonged Downhill Versus Uphill Treadmill Exercise

2020

AbstractOxygen uptake (V̇O2), heart rate (HR), energy cost (EC) and oxygen pulse are lower during downhill compared to level or uphill locomotion. However, a change in oxygen pulse and EC during prolonged grade exercise is not well documented. This study investigated changes in cardiorespiratory responses and EC during 45-min grade exercises. Nine male healthy volunteers randomly ran at 75% HR reserve during 45-min exercise in a level (+1%), uphill (+15%) or downhill (−15%) condition. V̇O2 , minute ventilation (V̇E ) and end-tidal carbon dioxide (PetCO2) were recorded continuously with 5-min averaging between the 10th and 15th min (T1) and 40th and 45th min (T2). For a similar HR (157±3 bpm…

Do elite endurance athletes report their training accurately?

2013

Purpose:The purpose of this study was to validate the accuracy of self-reported (SR) training duration and intensity distribution in elite endurance athletes.Methods:Twenty-four elite cross-country skiers (25 ± 4 y, 67.9 ± 9.88 kg, 75.9 ± 6.50 mL · min−1 · kg−1) SR all training sessions during an ~14-d altitude-training camp. Heart rate (HR) and some blood lactate measurements were collected during 466 training sessions. SR training was compared with recorded training duration from HR monitors, and SR intensity distribution was compared with expert analysis (EA) of all session data.Results:SR training was nearly perfectly correlated with recorded training duration (r = .99), but SR training…

Hemichorea associated with varicella-zoster reinfection and endocarditis. A case report.

1985

A 20-year-old woman developed transient right-sided hemichoreatic movements after household exposure to varicella-zoster. Some days before the appearance of involuntary movements a vesicular rash had occurred. About 6 months later an elevated IgG serum titer against varicella virus was found and two-dimensional echocardiography showed signs of an endocarditis. During the following 2 months the IgG value returned to within the normal range and the choreatic movements disappeared almost totally. The possibility is discussed that endocarditis had been caused and maintained by serum antibodies to varicella-zoster virus which cross-reacted with valvular tissue. Embolization to the region of the …