IsoMax 6x6: 1-Rep Max Testing

After 12 weeks of dynamic exercise for conditioning, fat-burning, and strength, I decided it was time for an isometric training block to give my joints a break. I chose the 6x6 program for strength, some hypertrophy, and hopefully tendon strength. Chrys Johnson has a good video explaining the what, why, etc. of 6x6.

1-Rep Max Test Results in Pounds:

Zercher Lunge - 80.4 (based on weaker leg scores)
Overhead Press - 103.4
Curl - 154.7

The plan is to do each exercise with the target muscles at the longest possible lengths, as inspired by recently published research that found greater carryover to dynamic performance, compared to isometric training at shorter muscle lengths. Thus the IsoMax strap numbers and body positions for the 3 exercises are:

Zercher Lunge - Strap #6 - I copied what Red Delta Project does in this video, except I don't use a weight vest, and the bar is set lower, to get my body as close as possible to the bottom of an ATG split squat, while still being able to get under the IsoMax bar. The quads and calf muscles are at a pretty good length

Overhead Press - Strap #20 - This is very close to the start position of the double kettlebell press. The triceps, anterior delts, and chest muscles are at a good stretch.

Curl - Strap #9 - The IsoMax bar is as low as possible, so it practically rests on the thighs. Thus the arms are close to straight, so that the biceps are at a pretty good length. To prevent any flareup of elbow tendonitis, I use the spiraling external rotation technique taught in this video. To protect the back, I imagine my chest being pulled up, and squeeze the glutes nice and hard, before I even begin pulling the bar. Finally to ensure bicep activation, I pull my elbows back. The combination of the external rotation technique, hard-working core (abs, glutes, etc.), and stretched biceps results in a 150-ish lb. force output, compared to when I first tried a bicep curl on the Isochain in late 2020 and was struggling to generate 30lbs. of force. People who prefer to isolate the biceps more in their training might consider what I'm doing to be cheating, but since I no longer feel isometric rowing is safe for my low back, this curl variation is all I have left for working on pulling strength, with as much force as possible. My pullup rep max is currently 8. It will be interesting to see if the rep max goes up after a couple of weeks of training with this isometric curl variation. In theory there should be an increase, because I use the same muscles (abs, external rotators, upper back, biceps) - especially in the upper half of the pullup - and the same spiraling external rotation technique when I do pullups. Presumably there will be some sort of relationship between any increase in max force in this curl, and repetition max - but data gathering will have to come later.