The ISWT profile calculates all outcome measures that can be derived from the distance walked on the ISWT and makes them readily available for the healthcare professional. The reference equations can be otherwise difficult to calculate manually and store as physical records. This guideline is valid for use only for individuals in the age range of 18-83 years. Measurement of exercise capacity is widely used in the rehabilitation of patients with cardiac and chronic respiratory disease as exercise intolerance is one of their typical features. The objective assessment through a cardiopulmonary exercise test gives an idea of the baseline outcome parameters which can be rechecked for any improvement after giving a specific intervention. Maximal cardiopulmonary exercise testing also helps to assess the safety of exercise, to define the factors contributing to exercise limitation, and to identify a suitable exercise prescription. The cardiopulmonary exercise test (CPET) typically done on a cycle ergometer is considered as the gold standard for determining maximal exercise capacity. However it is not possible to perform CPET often as it needs a laboratory and cycling is not a functional activity for many patients. The ISWT is a field walking test that evaluates the maximal exercise capacity based on total distance walked by the individual during the test. Compared to a CPET, it is more feasible to perform an ISWT and is therefore more commonly used especially during rehabilitation. The test includes 12 levels of speed that are dictated by external audio signal and the participant is expected to walk (or run) around a 10 metre course for each level. The initial speed is 0.5 metres (m)/ second (s), that is, the participant covers 10m in 20s. The speed progressively increases by 0.17 m/s (distance remains constant, time given to complete the course reduces). Similar to a CPET, patients are subjected to increasing workloads in ISWT till their limit of tolerance. The test is discontinued when the patient cannot keep up with the speed, if they experience any signs or symptoms or when they reach 85% of their predicted maximum heart rate The distance that is expected to be walked by an individual in the ISWT can be predicted from their age (in years), gender and body mass index (BMI) with the help of reference equation as follows: ISWT predicted distance (metres) = 1449.701 − (11.735 × age) + (241.897 × gender) − (5.686 × BMI) where male gender = 1 and female gender = 0, age is between 18 to 83 years, BMI = weight (in kilograms)/ square of height (in metres) The change in the distance walked in the ISWT can be used to evaluate the effectiveness of an exercise training program and / or to track the change in exercise capacity over time. The minimal important difference in the distance walked is an improvement between 35m to 58m. The patient’s exercise capacity can also be represented by calculating the percentage of the predicted distance walked by the patient. % predicted distance = Distance walked/ ISWTpredicted distance * 100 where distance is in metres. Maximal oxygen consumption (VO2max) is a traditional measure of cardiorespiratory exercise capacity. Maximal oxygen uptake (VO2max) was defined by Hill and Lupton in 1923 as “the oxygen intake during an exercise intensity at which actual oxygen intake reaches a maximum beyond which no increase in effort can raise it‟, thereby defining the limits of the cardiorespiratory system. Maximal laboratory exercise tests precisely measure VO2max. VO2peak is the highest value of VO2 attained on a particular test, most commonly an incremental test, that brings the subject to the limit of tolerance. It defines the highest value attained by the subject during the test regardless of his efforts and not necessarily the highest value attainable by him. However research suggests that the VO2peak attained on a maximum effort incremental test in subjects exercising to the limit of tolerance is likely to be a valid index of VO2max. During the ISWT there is a linear relationship between walking speed and VO2, and VO2 peak can be predicted from the distance walked. VO2peak= (4.19+ (0.025 * distance walked))*weight where VO2peak is in ml•min-1 and distance is in metres. Peak exercise capacity is calculated from the distance walked on ISWT by the following reference equation: W peak = 0.0025*distance walked × weight + 10.19. where W peak is the peak exercise capacity in watts, distance walked is in metres, weight is in kg