Silly Act !

Started going to gym after balloning from eating good food for sometime now and pants no more fit...only 1gets in perfectly now :(.....The trainer asked to do a 10 minute walk on Treadmill and I happened to do some silly experiment....while the treadmill was running at 5 Km/hr, I tried stepping out ...I planned to do for both legs together on the side but did only one ....and zoop i went down and got some bruises at knee and lower leg. Think of a reason why I did such act ?? ahh i dont have a reason ....just felt like trying it out ...and so some consequences.... thankfully not much injury.