How Does This Sentence Sound?

I found a very interesting English sentence in an entry. "I alternate between stretching and light strength training for 30 minutes every day." There's no mistake, so a native English speaker said, "it's perfect."  I also think so. However, if I translate the sentence into Japanese, it comes to  毎日30分間、ストレッチと軽い筋力トレーニングを交互にやっている, and it sounds like "I do 30 minutes each day, alternately between stretching and light strength training."  It sounds like the author does both every day.   I don't think the author doesn't mean to say that. The author wants to say that she does stretches one day for 30 minutes and the next day, does light strength training for 30 minutes.  I'm wondering whether the original sentence means that she does each of them on different days in English. If the sentence didn't mean that, how would you say it?  Doesn't "every other day" 一日おきに work well? I'm curious!