The Impact of Acute Mental Stress on Handgrip Exercise Induced Brachial Artery Flow-Mediated Vasodilation
Bibliographic record
Abstract
Chronic stress is a risk factor for cardiovascular disease however the role of endothelial function in this relationship remains unclear. Although controversial, it has been shown that acute mental stress can impair brachial artery flow mediated dilation (FMD) following a reactive hyperemia (RH) induced increase in shear stress (SS). However it is currently unknown whether acute stress impairs FMD following exercise induced increases in SS. It is important to investigate FMD using exercise induced increases in SS because the stimulus is controlled and more physiologically relevant compared to the transient increase in SS associated with RH. PURPOSE: to determine whether an acute increase in mental stress results in a similar attenuation of brachial artery FMD following RH and handgrip exercise (EX) induced increases in shear stress. METHODS: brachial artery (BA) FMD was investigated in 16 male subjects (18-28 yrs) with Echo and Doppler ultrasound. Each subject participated in two experimental visits: Visit A RH induced increases in shear stress to determine FMD; Visit B EX induced increases in SS to determine FMD (visits order counterbalanced between subjects). SS estimated by shear rate (SR= BA blood velocity/ BA diameter). FMD tests were performed 10 min after both a control task (CT- count upwards from 1) and a 20min mental stress task (ST- speech task followed by mental arithmetic (based on the Trier Social Stress Test)). Results are means ± SE. RESULTS: The ST was successful in elevating hemodynamic variables: average mean arterial pressure (MAP) increased 19.77 ± 2.06 mmHg during the stress task vs. 4.28 ± 1.57 mmHg during the CT (p=<0.001). Heart rate (HR) increased 12.71 ± 2.07 bpm during the ST vs. 4.50 ± 0.49 bpm during the CT (p= 0.005). The ST had no impact on the SR stimulus magnitude in either test; Post CT RH SR area under the curve (AUC) 5117.75 ± 376.6 s-1 vs. Post ST RH SR AUC 4364.08 ± 403.70 s-1 (p= 0.132). Post CT SR during the last min of handgrip exercise was 58.90± 0.91s-1 vs. 59.30 ± 1.29 s-1 Post ST (p=>0.05). Post CT RH FMD was 5.34±0.56% vs. Post ST RH FMD 4.55± 0.47%; Post CT EX FMD was 4.66± 0.73% vs. Post ST EX FMD 5.46± 0.62% (p= >0.05). CONCLUSION: There was no impact of acute mental stress on FMD following either an RH or an EX induced increase in SS. Supported by Canada Foundation for Innovation and NSERC.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".