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.

Background: Uphill walking is biomechanically stressful. Changes in plantar pressure, is one of the important predictors of this stress and increased risk of foot injuries. It has been reported that civilians as well as different occupational workers have to walk over uphill gradient with footwear which may cause changes in plantar pressure. Till date published data on plantar pressure is not available of Indian population during shod walking with uphill gradients. Aims and Objective: The present study was aimed to generation of data base on plantar pressure and find out the effect of shod walking (wearing occupational boot) on plantar pressure at different uphill gradients. Materials and Methods: Twenty healthy male participated in this study. Plantar pressure was recorded using the pressure measurement system during walking at 4 km/hr speed on treadmill at level and different uphill gradients. Results: It was observed that the PP at all the five regions of both right and left foot (Forefoot, Mid-foot, Medial, Lateral, Heel and Overall) increased gradually along with the increase in gradients. There was significant increase of 8.94%, 9.93%, 18.22%, 16.06%, 10.27%, 12.92% respectively at left forefoot, mid-foot, heel, medial, lateral and overall regions at 10% gradient compared to level walking. Similarly, in right foot the increase was observed 8.20%, 10.82%, 14.28%, 13.75%, 8.27%, 10.88% in respective foot regions compared to level walking. Conclusion: Observations of the present study stated that with increasing gradient plantar pressure at various foot regions increased in both feet in comparison to level walking, maximum plantar pressure observed in heel region in both feet in comparison to other studied regions. This data will be considered as normal planter pressure value of adults at level and uphill gradients shod walking and may be utilized for prognosis of foot disorders and efficacy of treatment modalities of population comparable with studied individuals (for similar age, height and weight).