trotting with tight strides

Question
QUESTION: hello. i have attached a video link. in that, can you please figure out which horses are trotting with tight strides? the below is the video link.

http://www.youtube.com/watch?v=g-_14XzD0hY

ANSWER: Hi - I looked at some of the video, and it is quite difficult to determine from that which of the horses would have a tighter stride.  What you want to look for when determining if a horse has a tight stride is the extension of the legs - look at the hoof prints when the horse walks, with a long stride, the back hooves may overlap the front. In a tighter stride, the hind foot will not extend as far forward as the front feet so you will have 4 deistinct hoof prints.  There are advantages and disadvantages with both types of strides.

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QUESTION: thanks for the answer. may i know why the leading horse's foreleg hitting the ground harder as if trotting roughly?

Answer
The horse in front - the buckskin (tan) at times is actually breaking from a trot into a canter. This may be what you are seeing. The trot should be an evenly spaced 2 beat gait - with opposite legs hitting the ground at the same time - right front/left rear and left front/right rear.