Evidence map›Paper›PMID 26689430›Full record

ArticleBiomedical engineering online2015

Identification of heart rate dynamics during moderate-to-vigorous treadmill exercise.

Kenneth J Hunt, Simon E Fankhauser, Jittima Saengsuwan

Abstract read
In one paragraph

Article in Biomedical engineering online, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers.

0numbers the graph read from it
0cells of the map it votes in
9citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

9 citing papers in PubMed.

  1. Trial
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  7. Robust control of heart rate for cycle ergometer exercise.Medical & biological engineering & computing · 2019
    Article
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

3 authors.

Kenneth J HuntDivision of Mechanical Engineering, Department of Engineering and Information Technology, Institute for Rehabilitation and Performance Technology, Bern University of Applied Sciences, 3400, Burgdorf, Switzerland. kenneth.hunt@bfh.ch.
Simon E FankhauserDivision of Mechanical Engineering, Department of Engineering and Information Technology, Institute for Rehabilitation and Performance Technology, Bern University of Applied Sciences, 3400, Burgdorf, Switzerland. sfanky_1990@bluewin.ch.
Jittima SaengsuwanDivision of Mechanical Engineering, Department of Engineering and Information Technology, Institute for Rehabilitation and Performance Technology, Bern University of Applied Sciences, 3400, Burgdorf, Switzerland. jittima.saengsuwan@bfh.ch.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundHeart rate can be used to prescribe exercise intensity for development and maintenance of cardiorespiratory fitness. The aim of this study was to identify the dynamics of heart rate response during moderate-to-vigorous treadmill exercise and to explore parameter dependencies with respect to time, intensity level and step-change direction. The focus was on simple approximate models for subsequent design of heart rate control systems.

methods24 healthy, able-bodied male subjects each did two separate, 35-min tests on a treadmill, one at moderate and one at vigorous intensity. Each test had four individual upward and downward steps (1-4). Heart rate responses were modelled as first-order transfer functions with steady-state gain k and time constant [Formula: see text]. Models were estimated both for the overall testing periods and for individual step responses within each test.

resultsThere were no significant differences in the overall mean values of k [24.3 vs. 24.1 bpm/(m/s), [Formula: see text]] and [Formula: see text] (55.7 vs. 59.5 s, [Formula: see text]) between the two intensity levels. The overall nominal gain for both conditions was [Formula: see text], 21.9-26.6 bpm/(m/s) (mean [Formula: see text] standard deviation, 95 % confidence interval), and the overall nominal time constant was [Formula: see text], 50.9-64.3 s. Analysis of models estimated from the individual steps revealed a significant difference in steady-state gain k for upward and downward steps [30.2 vs. 23.6 bpm/(m/s), [Formula: see text]], but no difference in time constant [Formula: see text] between these two directions (57.5 vs. 54.4 s, [Formula: see text]). For gain k, there was no significant main effect of intensity ([Formula: see text]) or intensity-time ([Formula: see text]) interactions, but there was a significant main effect of time ([Formula: see text]). Pairwise comparison with respect to time showed a significant difference between the upward steps at times 1 and 3 [33.0 vs. 27.3 bpm/(m/s), [Formula: see text]], but no significant difference between the downward steps at times 2 and 4 [24.4 vs. 22.8 bpm/(m/s), [Formula: see text]]. For time constant [Formula: see text], there were no significant main effects of intensity ([Formula: see text]) or time ([Formula: see text]), or intensity-time interactions ([Formula: see text]).

conclusionsThe tight CI-bounds obtained, and the observed parameter dependencies, suggest that the overall nominal model with [Formula: see text] and [Formula: see text] might serve as the basis for design of a linear time-invariant (LTI) feedback system for real-time control of heart rate. Future work should focus on this hypothesis and on direct comparison of LTI and nonlinear/time-varying control approaches.

Indexed as

Exercise TestAdolescentAdultHeart RateHumansMaleMiddle AgedYoung Adult

Identifiers

PMID26689430
PMCPMC4687158

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.