Intervals are ridiculous – 30 Day - Plank Challenge Review

Day 2 has a 50% increase in time over Day 1. The next increase is a 33% increase. It drops from there until Day 9, when there is a greater than 70% increase. Nothing is methodical for increasing and most exercise people promote increases of 2-5%.
Review by monkey in Seattle on 30 Day - Plank Challenge.