Back ache via deadlift

Phase 1 Week 2 Day 2/2

The exercises in vjb novice weights took less time than vjb bodyweight. It just took 1/2 an hour.

Deadlift feels like I'm trying to get a back ache when I'm old. The day after my back aches. I did mixed grip, used my legs to lift the bar with 1RM to the knee level then from there I used my back to pull the bar up thus fully extending my knees meaning till my whole body is straight. My back is slightly curved during the straightening above. Wrong technique?

I am sick during this session. I have a fever and vomit. I did this only after I felt I was well enough but still slightly sick, like experiencing only almost moderately painful head ache.

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