My mom is coming to visit us for a whole month!
However, she won't be bringing along her greatest asset: cooking. She has gained a bit of weight over the last few years because of some health issues and we have talked about getting her back in shape while she's here. We have a gym in our apartment building and I plan on giving her a 20-minute workout every other day.
The main thing I want to do is prevent DOMS as much as possible. She won't be inclined to stick with it if she's in pain. She's in her 60s and she's not trying to gain a muscular appearance, but I don't want to focus on too much cardio. I feel like that won't be productive in helping her lose weight. I'm thinking of doing a full-body routine every workout- 2 compound machine exercises for push, pull and legs, 5 reps, 3sets, minimal weight.
Any suggestions for improvement? And, most importantly, any suggestions on limiting DOMS?
Without knowledge of her previous health issues it's a bit difficult to consider what would/wouldn't be safe for her. Unless she has previous experience with (any type of) weightlifting, I wouldn't introduce too complex movements and maybe just stick with machines. Seeing as you've indicated that the goal is to lose weight and to get her back into shape (by which I assume you mean some building of strength?); I would suggest at least some compound movements (or variants) like light deadlifts and (bodyweight)squats (or variants). Simply because these, also at a later stage in life, are movements made on a daily basis, and therefore would be beneficial for her in the longrun as well (think; getting out of bed, picking stuff up, cleaning, etc.). Additionally, as they recruit a large amount of muscles it'll help boost metabolism (bro-science, sure).
In my personal opinion, dedicating time for cardio in the gym is a waste of time. Especially when you're aiming at only dedicating 20-min every other day. For your mother to become/remain more active it would be much more beneficial to go for a daily walk, or something along those lines, which she would actually enjoy(?) instead of mindlessly being on a threadmill/bike facing a wall. In the sense that going for a walk wouldn't be a 'punishment or duty to be fulfilled' as opposed to going and being in a gym.
Considering DOMS, I doubt you'll be able to prevent it, unless you build it up very slowly/easily. Simply because fitness movements are always slightly different than daily movements, and thus load/recruit muscles differently. As mr.turbo said, just focus on mastering technique, and just slowly build up and see what&where you can increase. In a few weeks time your mom and you should be able to determine what is feasible and effective resistance and what is not. Simply because you only wish to dedicate 20min eod, I wouldn't push for a full-body exercise, simply due to time constraints, and also being harsh on the recovery taking into account her age.
Good luck to you and you're mom.