You need to make a composite image with several tracks of video overlaying each other with different video levels -- probably need to slow the motion too and blur the image etc.. -- Might be some plugin for this? -- This tutorial has some of the techniques needed to get you going. Couldn't find a tutorial that does exactly what you wanted.
Asymetric motion blur might give you the effect you're after, assuming the camera was locked off.
If the camera is moving in any manner you need quite sophisticated tools which is what I suspect is bought to bear to produce the kinds of effects I see used in sports promos and the like. If you don't have the tools to isolate subject elements from background you can still do it in Vegas just a lot of work manually keyframing masks.
One shot I recall from local TV is a javeline thrower. Camera tracks him as he runs then just as he throws everything except the javelin goes into freeze frame. Javelin continues with ghostly trail and camera moves around frozen stadium, pretty much I think this a bullet time effect which requires many cameras. However today with Imagineer and their Mocca product almost anything seems possible.
Add your clip to the time line and duplicate 5,6,7 times
Then from track 1 normal speed and on each level slightly increase the speed of each level
And add the comp mode of each level to each other, depends on your back ground and how the clip was shot
This way you will get a speed trail
or if you use velocity ramps adjust the t end points of the velocity ramp
Or with your 7 tracks on add composit …speed all the same just notch each track few frames forward
I can post a clip to give you some ideas
Depends on you footage but if you go to 3d comp on each track ,offset them in 3d space with speed ramp the results can be mindblowing
Rory
Edit
For those who don’t know….don’t forget to drop your opacity levels right down of each of the add comp layers otherwise your image will overexpose