took the sled out for a proper workout this morning, wrangling it in and out of the car worked out ok after I got the technique right. I used the harness at the local sports field next to the playground. The weight of the sled plus my daughters weight and the extra drag for the grass gave me one hell of a workout in a very short period of time, my hamstrings and glutes are seriously feeling the results this arvo, not to mention the huffing and puffing from the cardio aspect. I am going to have to find my HR monitor to estimate the calorie burn for a 15 minute intense strength session with large anaerobic and aerobic components.