A computer-implemented method for use with a user performing an exercise, comprising: monitoring, with a first sensor, athletic activity of the user while performing the exercise; monitoring, with a second sensor, the athletic activity of the user while performing the same exercise; selecting, by a computer processor, one of the first sensor and the second sensor for use in calculating an energy expenditure estimate of the user corresponding to the monitored exercise, wherein the selection is a function of an exercise type of the exercise; wherein the exercise includes multiple repetitions, and wherein the method comprises, for each repetition: generating a completeness modifier which corresponds to how well the form of the user corresponds to a desired form for the exercise, and which varies from repetition to repetition, based on monitoring the form of the user as the user performs the exercise using detected sensory location information from the selected one of the first sensor and the second sensor; wherein the completeness modifier indicates what percentage of full movement was achieved for each respective repetition when performing the exercise; calculating the energy expenditure estimate of the user based on a completeness modifier generated as a weighted average using a decaying function whereby more recent completeness modifiers are weighted more heavily than less recent completeness modifiers; wherein the energy expenditure estimate is based on a basal metabolic rate of the user and wherein the calculating of the energy expenditure estimate applies the following equation: calories burned = BMR ∗ (activity modifier) ∗ (completeness modifier), wherein BMR is the Basal Metabolic Rate of the user, and the activity modifier is an adjustment corresponding to a type of the exercise; wherein the activity modifier varies according to one or more of pace, type of exercise, duration, and/or wherein the activity modifier is determined from predetermined values assigned to an exercise or movement that the user is prompted to perform, or information from a MET table correlated to an exercise; displaying, by a first display device associated with the selected sensor, the energy expenditure estimate of the user; and displaying, on a second display device associated with the non-selected sensor, the same energy expenditure estimate of the user displayed on the first display device associated with the selected sensor. monitoring, with a first sensor, athletic activity of the user while performing the exercise; monitoring, with a second sensor, the athletic activity of the user while performing the same exercise; selecting, by a computer processor, one of the first sensor and the second sensor for use in calculating an energy expenditure estimate of the user corresponding to the monitored exercise, wherein the selection is a function of an exercise type of the exercise; wherein the exercise includes multiple repetitions, and wherein the method comprises, for each repetition: generating a completeness modifier which corresponds to how well the form of the user corresponds to a desired form for the exercise, and which varies from repetition to repetition, based on monitoring the form of the user as the user performs the exercise using detected sensory location information from the selected one of the first sensor and the second sensor; wherein the completeness modifier indicates what percentage of full movement was achieved for each respective repetition when performing the exercise; calculating the energy expenditure estimate of the user based on a completeness modifier generated as a weighted average using a decaying function whereby more recent completeness modifiers are weighted more heavily than less recent completeness modifiers; wherein the energy expenditure estimate is based on a basal metabolic rate of the user and wherein the calculating of the energy expenditure estimate applies the following equation: calories burned = BMR ∗ (activity modifier) ∗ (completeness modifier), wherein BMR is the Basal Metabolic Rate of the user, and the activity modifier is an adjustment corresponding to a type of the exercise; wherein the activity modifier varies according to one or more of pace, type of exercise, duration, and/or wherein the activity modifier is determined from predetermined values assigned to an exercise or movement that the user is prompted to perform, or information from a MET table correlated to an exercise; displaying, by a first display device associated with the selected sensor, the energy expenditure estimate of the user; and displaying, on a second display device associated with the non-selected sensor, the same energy expenditure estimate of the user displayed on the first display device associated with the selected sensor. calories burned = BMR ∗ (activity modifier) ∗ (completeness modifier), wherein BMR is the Basal Metabolic Rate of the user, and the activity modifier is an adjustment corresponding to a type of the exercise; wherein the activity modifier varies according to one or more of pace, type of exercise, duration, and/or wherein the activity modifier is determined from predetermined values assigned to an exercise or movement that the user is prompted to perform, or information from a MET table correlated to an exercise; displaying, by a first display device associated with the selected sensor, the energy expenditure estimate of the user; and displaying, on a second display device associated with the non-selected sensor, the same energy expenditure estimate of the user displayed on the first display device associated with the selected sensor.