Cardio
Cardio is a great tool for improving heart health, recovery, and overall fitness. The thing is, if you’re experiencing a solid amount of stress in your life outside the gym, adding cardio probably is going to do more harm than good. So the first step, if you want to add cardio, is making sure your life outside the gym has a reduced amount of stress.
If you’re experiencing medium to high stress:
Walk daily when possible. Aim for 5-8k steps per day.
If you’re experiencing low stress:
Aim for 1–3 dedicated cardio sessions per week if your goals include cardiovascular fitness. I would say 20-60 minutes of zone 2 work.
In addition, I would aim for 10-12k steps per day of intentionally paced walking. Conversational, not out of breath pace.
Cardio supports your strength training. It shouldn't replace it.