Anyone do 2x20min intervals at LT power during their base season? I read that it takes more than the usual month or 6 weeks of longer LT intervals to really increase power at LT. My season (elite MTBer) ends this weekend and starts again in early April. Assuming I take 4-6 weeks of just fun riding (Sept, 1/2 of Oct): 1) when should I start doing 2x20s? 2) how many times per week? thanks.