Friction is a bitch!

When it comes to sled work only one thing matters...ATTITUDE!

Depending on the implement you are using and it's reaction to the surface (high or low friction) the load you put on may be massive or miniscule.

It doesn't matter.  When working sleds its ATTITUDE to get the job done that makes the difference.

Try working %EFFORT for time e.g. 30sec, 45sec, 60sec.  You can build up with efforts of ascending intensity just as you would for conventional strength lifts.

If you are on the same surface all the time that's a luxury, you can alter the weight accordingly. 

For those who work outside, particularly on grass, the surface is quickly affected by environmental conditions so you may have to adapt your load.  When that happens keep your focus on relative intensity.  Ask yourself how hard you are going.  If the answer isn't yet 100% load up and get moving! 

Great test of your INTEGRITY as an athlete!

JW