Heart rate as an estimator of oxygen consumption during manual postal delivery. by Oja P, Ilmarinen J, Louhevaara V Key terms: heart rate; heavy work; manual postal delivery; oxygen consumption; prediction This article in PubMed: www.ncbi.nlm.nih.gov/pubmed/7134920Scand ; work environ health 8 (1982) [29][30][31][32][33][34][35][36] Heart rate as an estimator of oxygen consumption during manual postal delivery by Pekka Oja, PhD,I, 2 Juhani IImarinen, PhD,1 Veikko Louhevaara, LSc 1 OJA P, ILMARINEN J, LOUHEVAARA V. Heart rate as an estimator of oxygen consumption during manual postal delivery. Scand j work environ health 8 (1982) 29-36. Nine young healthy postmen performed three progressive maximal exercise tests (on a bicycle ergometer and with and without a 10-kg shoulder bag on a treadmill) for which the least-squares regression equations of heart rate (HR) on oxygen consumption (V02) were established. HR and V02 were then measured during five modes of simulated postal delivery: on level ground by foot (F), bicycle (B), and push-cart (C) and on stairs by foot (S/F) and push-cart (SiC). The respective work HR values were inserted into the three regression equations established for HR/V02, and V02 was solved for. The estimated V02 values tended to be systematically higher than the measured ones. The best regression proved to be that established for the treadmill plus mailbag; the regression coefficients between the measured and estimated V02S were higher than 0.75, and the percentage differences between the means of the measured and estimated values were no more than 10 Ofo for F and B delivery. All the regressions yielded inaccurate estimations of V02 for C, S/F and SIC delivery. It was concluded that HR is acceptable as an estimator of V02 only when the test work closely resembles the muscle work in the job.Key terms: heavy work, prediction.The direct means available for measuring oxygen consumption {V0 2 ) under field conditions are rather cumbersome. Thus many attempts have been made to develop methods for estimating energy consumption. Heart rate is one attractive measure for this estimation because of its linear dependability on V0 2 , within limits, during certain types of muscular work. Indeed, heart rate has been used as the basis for estimating both the daily energy expenditure (5, 6, 12, 15) and V0 2 of specified work such as coastal fishing (3, 13), housekeeping activities (2), building construction work (1), surgical operations (10), and postal delivery (11).Fordham et al (7) compared the measured and predicted V0 2 in light industrial work and found the "prediction

Age and sex as determinants of the relative aerobic strain of nonmotorized mail delivery. by Oja P, Louhevaara V, Korhonen O The relative aerobic strain (RAS) of nonmotorized mail delivery was assessed in 54 Finnish maH carriers who represented both sexes, the entire work~ge range and both downtown and suburban delivery districts. The mean RAS of the entire delivery time was 55 Ofo of the maximal oxygen uptake (mllkg . min). It was higher for women than for men, and higher for suburban than for downtown delivery. The RAS tended to increase systematically with age after the age of 50. The work strain of mail carriers of over 50 years of age, especially of older women carriers in suburban areas, was concluded to be high enough to lead to possible excessive strain on the workers.