A brief history of exercise clearance and prescription: 1.	The era of heart rate recovery curves
Creators: name: Nsenga Leunkeu, Angeline
name: Shephard, Roy J.
name: Ahmaidi, Said
Publisher: name: The Health & Fitness Journal of Canada
Year: 2014

description: Objective. The aim of this 2-part article is to provide a brief chronicle of the development of exercise clearance and prescription procedures over the past century, with particular reference to Canadian innovations. Part 1 considers the era when any advice was based upon pulse rate recovery curves, with examples of specific approaches from Canada, the United States, Britain and France. Recent laboratory data are presented for one such test (that of Ruffier and Dickson), and these findings are compared with the response to a more modern field test of endurance performance, the 20-m shuttle run test.
 
Methods. Volunteers for the empirical recovery tests were 12 moderately active male students recruited from the University of Amiens Faculty of Sports Sciences. Each subject performed a Ruffier-Dickson test on 2 days, followed on the second day by a 20-meter shuttle run (20-MSR). Parameters measured for the 20-MSR were the resting heart rate, the heart rate at the immediate end of the test, and the heart rate after 1 minute of recovery, with evaluation of the predicted maximal oxygen intake (O2max), the predicted maximal aerobic velocity (MAV) and recuperation indices based on application of the Ruffier-Dickson formulae.
 
Results: The 20-MSR prediction of maximal aerobic power was much as in average young adults, with a value (mean  SD) of 46.8  3.5 ml/[kg.min]. Indices calculated for the two Ruffier tests showed day-to-day stability (Ir1 10.9  2.5 , Ir2 = 10.2  3.3). However, based on published norms, the average scores suggested a relatively low level of physical fitness. A much higher recuperation index (IrN = 23.8  4.1) was calculated for the shuttle run data than for the Ruffier tests. Corresponding indices obtained by applying the Ruffier-Dickson formulae were 11.1  3.3, 11.7  3.3 and 29.4  4.1. The scores obtained in the duplicate Ruffier tests were fairly closely correlated with each other, with similar mean scores and no significant change in the ranking of subjects. Application of the Ruffier-Dickson formula also gave comparable scores on the 2 occasions. There were moderate correlations between the standard Ruffier test indices and 20-MSR shuttle run Ruffier indices (r = 0.63-0.65). However, the ranking of subjects based on Ruffier test scores bore little relationship to a classification of aerobic fitness based upon 20-MSR predictions of maximal oxygen intake .
 Conclusions: Although the heart rate recovery tests undertaken in the first half of the 20th century gave consistent day-to-day scores within a given laboratory, the values obtained depended heavily on test details such as posture when measuring heart rates and the timing and duration of pulse counts. Moreover, in the selected example (the Ruffier-Dickson test) the ranking of individuals bore little or no relationship to more modern measures of endurance fitness such as maximal oxygen intake or maximal aerobic velocity. Recovery test scores had an uncertain physiological basis; most indices probably reflected a combination of the immediate cardiac response to moderate exercise, achieved mainly by an increase of stroke volume in a fit individual, but by an increase of heart rate in those who are unfit, and the rate of recovery from this stress. However, the information was of limited help in terms of exercise clearance and the prescription of appropriate physical activity, pointing the need to develop reliable, objective and evidence-based procedures for this purpose.
description: The Health &amp; Fitness Journal of Canada, Vol 7 No 1 (2014)