Some points to be made.
1. Zweihanders weighed on average 2-3kg, this is about 4 to 6 pounds. Zweihanders above 3kg were considered ceremonial unless you're Grutte Pier
2. If we were to include fatigue then everybody could only run for a while, fight for a little while, and horses could only run for a little while. If we were to include the fatigue of swinging a 2lb saber then we should include the fatigue of thrusting a 12 pound musket. It would be a mess to include fatigue for everybody.
3. The topic at hand is the need for a buff to saber briquets, which they do deserve.