The purpose of this investigation was to examine the validity of the exercise intensity of which lactate increased 0.1 mmol/l from baseline level (METs@LAr+0.1), as for the practical assessment of lactate threshold (LT), in younger adults. Thirty-two apparently healthy younger adults (21±1yr., 167.5±10.2cm, 58.2±9.4kg) performed submaximal bench stepping test, in order to determine the LT and METs@LAr+0.1. The LT (8.6±1.1METs) and METs@LAr+0.1 (8.7±1.4METs) were not significantly different, with the strong correlation (r=0.925, p<0.001). The mean error (%), the standard error of estimation (%) and the total error were -0.1±0.6 METs (-0.5±6.7%), 0.44 METs (5.1%) and 0.53 METs, respectively. Furthermore the lower and upper limit of agreement were -1.1 METs (-13.2%) and 1.0 METs (11.6%), respectively. These results suggest that METs@LAr+0.1 can estimate the LT with ±15% of error. Thus the METs@LAr+0.1 may be a valid and useful assessment of LT in younger adults.