Weight lifting question

I used to hit everything same day but found time the issue, now I do a 3 day cycle with a rest day as and when I need it. Had 2 this week so tomorrow will start mid way thru my 3 workout cycle. Seems to work well as I hit each muscle group harder knowing they will get a rest

If you are just going with really light weights and super high reps, you can lift everyday for the whole body because it is working the Type 1 muscle fibers that are endurance. If you are going heavier with the weight and doing lower reps (less then 15 reps), then you have to allow the various Type 2 muscle fibers (There are multiple types of type 2 fibers) at least 48 hours rest before you work them that way again so that they have time to heal.

Basically, if you are doing resistance training and hitting the type 2 fibers you are doing microscopic damage to the muscle cells. While that sounds counter productive, it's actually how the body sees the stimulus to store glycogen for future workouts and eventually to build bigger and more muscle fibers. This is why some people will tell you to do weight training ever other day or to alternate muscle groups (upper body one day, lower body the next).

So, to answer your original question, all of the above are correct. You just have to design a plan that works for the type of training you are doing and the days of the week you want to workout. Personally, I go heavy enough most of the time that 48 hours isn't enough rest for my muscles, so I do 1-2 body parts a day 5-6 days a week and only work each body part one time per week.

i go 5 days a week i do cardio first then train a different body part each day.