Home

Fatigue

So how long does it take to do a rep? Some would have you believe that an optimal rep actually takes around 10 seconds!!!! !!!!! I could of course move really slowly but instead I just lift at whatever rate allows me to use the most weight or most reps - from a strength perspective this is far more productive than moving really slowly.

Fatigue

Continuing on from Jump with my analysis of exercises. I recently did the Sumo. The range of motion for these reps, as determined from pixel distances, is 340 mm. SI units are used unless stated otherwise.

The figures are for the positive part of the reps and look at bar time.

Here I compare a 2 rep max to an 8 rep max (I perhaps had a rep in each but these days I rarely go to failure);

233 kg

233 kg × 2 reps (9th April 2008)

rep sec m/s work power imp
1 1.933 0.176 776.0 401.5 4416.8
2 2.100 0.162 776.0 369.5 4798.4

2 reps

With only two reps the second rep is slower than the first due to fatigue.

213 kg

213 kg × 8 reps (11th April 2008)

rep sec m/s work power imp
1 1.434 0.237 709.4 494.7 2995.4
2 1.233 0.275 709.4 575.4 2575.5
3 1.300 0.261 709.4 545.7 2715.5
4 1.300 0.261 709.4 545.7 2715.5
5 1.300 0.261 709.4 545.7 2715.5
6 1.333 0.255 709.4 532.2 2784.4
7 1.433 0.237 709.4 495.1 2993.3
8 1.700 0.200 709.4 417.3 3551.0

8 reps

With reps I always find the second rep is faster than the first - from thereon the reps get slower.

Discussion

So what have I learned from this? That reps get slower but mainly for the last reps. I assume this is a shallow exponential curve.

13th April 2008