Competitors were expected to clear the hurdles by jumping them completely, or gently touching the tail of the snowshoe on the front edge of the hurdle. The hurdles were the sturdy equestrian style and miscalculation in attempting to clear the hurdles was common... often resulting in broken showshoes and injuries.
Hurdle heights were eventually standardized at three feet (36 inches) and a formal rule was adopted in the 1878 Laws of Snow Shoe Racing that required full clearance of each hurdle. The standardization of the racing shoe to one and a half pounds with no less than ten inches of gut at the widest part was decided by a December 1871 convention of snowshoers from various Montreal clubs.
I don't believe this will ever become a winter Olympic sport!