BackgroundThe present study was undertaken to determine the effect of different uphill and downhill gradients on cardiorespiratory and metabolic responses of soldiers while carrying heavy military loads in two different modes.MethodsEight physically fit male soldiers with a mean age 32.0 ± 2.0 years, a mean height of 169.5 ± 4.9 cm, and a mean weight of 63.8 ± 8.4 kg volunteered for this study. Each volunteer completed treadmill walking trials at a speed of 3.5 km/h while carrying no external load, 31.4 kg load in a distributed mode (existing load carriage ensembles) and compact mode (new back pack) over 5 different downhill and uphill gradients (− 5, − 10%, 0, 5, 10%) for 6 min at each gradient. During the walking trials, heart rate (HR), oxygen uptake (VO2), respiratory frequency (RF) and energy expenditure (EE) were determined by the process of breath-by-breath gas analysis using a K4b2 system. The average of the last 2 min data from each 6 min walking trial for each individual was subjected to statistical analysis.ResultsAll parameters (HR, VO2, RF, and EE) gradually increased with the change in gradient from downhill to level to uphill. The distributed mode showed higher values compared to compact mode for all gradients, e.g., for VO2, there was a 10.7, 7.4, 5.1, 28.2 and 18.7% increase in the distributed mode across the 5 different gradients.ConclusionIt can be concluded from the present study that the compact mode of load carriage is more beneficial than the distributed mode in terms of cardiorespiratory responses while walking on downhill and uphill surfaces with a 31.4 kg load.

In many recent studies, moderate intensity aerobic exercise has been shown to improve mental performance. Majority of the studies have focused on the chronic effects of exercise, while studies on the acute effe cts of exercise on cognition have started to draw growing attention of the researchers. the main objective of the present study was to establish the fact that Queens college step test (Qct), a short duration step test exercise is a useful tool for improving mental performance of young adult population. ten healthy young male adults participated for the present study. they performed following cognitive tasks i.e. simple reaction time (Srt) for measuring speed of processing, stroop task for selective attention, during before exercise, immediate after exercise and 30 minutes after exercise. the performance times were recorded and carotid pulse was also measured immediately after the exercise. the finding of the study states that there was a significant decrease in Srt, and stroop task performance time immediately after exercise, 30 minutes after