Applied Ergonomics 34 (2003) 225–231 The effect of technique and shaft configuration in snow shoveling on physiologic, kinematic, kinetic and productivity variables Raymond W. McGorry*, Patrick G. Dempsey, Tom B. Leamon Liberty Mutual Center for Safety Research, 71 Frankland Road, Hopkinton, MA 01748, USA Received 2 June 2001; received in revised form 1 June 2002; accepted 1 December 2002 Abstract Arepeatedmeasures2  2factorialdesignusingapsychophysicalexperimentalmethodologywasperformedtoquantifytheeffect of shaft design (straight and bent shaft) and shoveling technique (forward and backward progression) on heart rate, perceived exertion, productivity, trunk kinematics and load kinetics. Ten male subjects performed four 8-min trials of snow shoveling on a pavedasphaltsurface.Themostnotablefindingwassignificantlylesstrunkflexionwiththebentshaft(41.4  )thanwiththestraight shaft design (49.2  ). The study results led to a recommendation of a bent-shaft shovel for the purpose of reducing trunk flexion. In the absence of any strong positive evidence and due to poor subjective response to backward progression while shoveling, this technique was not recommended. r 2003 Elsevier Science Ltd. All rights reserved. Keywords: Snow shovel; Bent handle; Trunk flexion 1. Introduction The preferred ergonomic intervention is to eliminate the potential exposure. Mechanized methods of snow removal (snow plows, snow blowers) might be typical interventions to reduce an occupational exposure, however the manual approach might be the only method available under intermittent, non-professional conditions. Snow shoveling can be strenuous work (Smolander et al., 1995), and has been associated with several types of musculoskeletal injury, most notably injuries to the shoulder and low back. Another class of injury associated with snow shoveling, often of much greater socio-economic impact, is a cardio- vascular incident such as myocardial infarction (Heppel et al., 1991; Whittington, 1977). There have been reports in the literature about shoveling of dry materials. The size of the shovel blade andtheeffectonproductivityduringshovelingmaterials such as ore and ash was investigated in the early 20th century. (Taylor, 1913). Frievalds (1986a) reviewed the relevant literature and reported that the parameters of the shoveling task had been well described, but that research into the elements of shovel design was lacking. Oneergonomicapproachtothedesignoftoolshasbeen modification of the handle. Tichauer (1978) reported that bending the handle of a pair of pliers used in an electronic wiring operation to produce a more neutral wristalignment,resultedinadecreaseinwristdisorders. The angle of the handle and the orientation of the work surface were reported to influence performance as well thepostureandmotionofthewristduringahammering task(SchoenmarklinandMarras,1989).Tosomeextent handle modification has been applied to, and investi- gated in the shovel. The shape, size and weight of the shovelblade,handlelengthandhandleanglewerefound to have a significant effect on energy expenditure, estimates of spinal compressive loads and performance by Frievalds (1986b). Degani et al. (1993) reported that the addition of a second handle lower on the shaft significantlyreducedEMGactivityofthebackextensors and in ratings of perceived exertion. Factors associated with snow shoveling have been reportedlessoftenintheergonomicsliterature.Areview of the literature identified only one study specific to manualsnowremoval,thatbeinganinvestigationofthe cardiovascular demands (heart rate, oxygen consump- *Corresponding author. Tel.: +1-508-435-9061; fax: +1-508-435- 8136. E-mail address: raymond.mcgorry@libertymutual.com (R.W. McGorry). 0003-6870/03/$-see front matter r 2003 Elsevier Science Ltd. All rights reserved. doi:10.1016/S0003-6870(03)00033-4