the best is to see photos or videos... about the stride lenght, feet only under body and higher frequency : This is soo complicated issue, than writing or talking about it only can make it more messy, however just picking 1 point to think about : - longer stride is also achieved by keeping the back leg further back - for little bit longer time - as the idea of pushing slightly back the leg - feet would propel the body forward. This requires increased felxibility in teh hip, ankles, and the longer muscless as calves, achilles, hams, but also teh front muscles of upper thight and lower abs region this issue can be better observed in racewalking or classical XC skiing, but is also clear by watching elite to run fast middel distance races instead or reaching with teh front leg further to the front, it is the back leg which pushes further back, while keeping teh body - the pelvic and chest region well in front straight up above the point of the front leg touchdown. This issue is not important for slow running, but as soon as the speed, faster pace etc becomes an issue, that biomechanicaly this is critical