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. 2021 Mar 5;11(1):5334.
doi: 10.1038/s41598-021-84803-8.

Validity and reliability of the 'Isometric Exercise Scale' (IES) for measuring ratings of perceived exertion during continuous isometric exercise

John W D Lea  1 , Jamie M O'Driscoll  1 , Damian A Coleman  1 , Jonathan D Wiles  2
Affiliations

Validity and reliability of the 'Isometric Exercise Scale' (IES) for measuring ratings of perceived exertion during continuous isometric exercise

John W D Lea et al. Sci Rep. .

Abstract

Isometric exercise (IE) interventions are an effective non-medical method of reducing arterial blood pressure (BP). Current methods of prescribing and controlling isometric exercise intensity often require the use of expensive equipment and specialist knowledge. However, ratings of perceived exertion (RPE) may provide a more accessible means of monitoring exercise intensity. Therefore, the aim of this study was to assess the validity of a specific Isometric Exercise Scale (IES) during a continuous incremental IE test. Twenty-nine male participants completed four incremental isometric wall squat tests. Each test consisted of five 2-min stages of progressively increasing workload. Workload was determined by knee joint angle from 135° to 95°. The tests were continuous with no rest periods between the stages. Throughout the exercise protocol, RPE (IES and Borg's CR-10), heart rate and blood pressure were recorded. A strong positive linear relationship was found between the IES and the CR-10 (r = 0.967). Likewise, strong positive relationships between the IES and wall squat duration (r = 0.849), HR (r = 0.819) and BP (r = 0.841) were seen. Intra-class correlation coefficients and coefficients of variations for the IES ranged from r = 0.81 to 0.91 and 4.5-54%, respectively, with greater reliability seen at the higher workloads. The IES provides valid and reliable measurements of RPE, exercise intensity, and the changes in physiological measures of exertion during continuous incremental IE; as such, the IES can be used as an accessible measure of exercise intensity during IE interventions.

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Conflict of interest statement

The authors declare no competing interests.

Figures

Figure 1
Figure 1
Knee joint angles used for the five consecutive 2-min stages of the incremental isometric exercise test (left to right: 135°, 125°, 115°, 105°, and 95°).
Figure 2
Figure 2
RPE scales presentation formats.
Figure 3
Figure 3
The relationship between the IES and CR-10 ratings of perceived exertion.
Figure 4
Figure 4
The relationships of the IES and CR-10 ratings with isometric exercise intensity (as a percentage of maximum).
Figure 5
Figure 5
The relationships of the IES and CR-10 ratings with the physiological measures of exercise intensity.
See this image and copyright information in PMC

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References

    1. Mancia G, et al. ESH/ESC guidelines for the management of arterial hypertension: The Task Force for the Management of Arterial Hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC) Eur. Heart J. 2013;34:2159–2219. doi: 10.1093/eurheartj/eht151. - DOI - PubMed
    1. Brook RD, Jackson EA, Giorgini P, McGowan CL. When and how to recommend “alternative approaches” in the management of high blood pressure. Am. J. Med. 2015;128:567–570. doi: 10.1016/j.amjmed.2014.12.029. - DOI - PubMed
    1. Wiles JD, Coleman DA, Swaine IL. The effects of performing isometric training at two exercise intensities in healthy young males. Eur. J. Appl. Physiol. 2010;108(3):419–428. doi: 10.1007/s00421-009-1025-6. - DOI - PubMed
    1. Cornelissen VA, Smart NA. Exercise training for blood pressure: A systematic review and meta-analysis. J. Am. Heart Assoc. 2013;2:e004473. doi: 10.1161/JAHA.112.004473. - DOI - PMC - PubMed
    1. Devereux GR, Wiles JD, Howden R. Immediate post-isometric exercise cardiovascular responses are associated with training-induced resting systolic blood pressure reductions. Eur. J. Appl. Physiol. 2015;115(2):327–333. doi: 10.1007/s00421-014-3021-8. - DOI - PubMed

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