I feel like this is something that a lot of people grapple with - how much cardio should I be doing / what kind of weight training should I be doing / what should my workout split look like? The simple answer is that you should have both cardiovascular and strength training in your regular routine. The more convoluted answer is that it depends on what your goals are!
So, to give you a personal case study, I have not done a workout in about 4 years that did not include both cardio and strength training in the same routine. First, I don't enjoy steady state cardio so instead I chose to include cardiovascular spikes (usually jumping rope) right there in between working sets. Second, the kind of weight lifting I do tends to require huge metabolic effort so that gives me cardio training benefits. Third, life is too short to do shit you hate so why not combine the things you enjoy?! The cardio-focused workouts that I do do (hahahaha, yes, I'm 5) all have some strength training elements to them... I guess I have a preference!
But this is me and the routine I have as my set-point. When I go through a 'cutting' phase in my programming, I do add some cardio sessions. Now, like I said, this is not something I enjoy so I use the step mill - the least hateful of the cardio machines - and I keep each session to 20mins, maybe 3x per week. This phase usually lasts no longer than 8-12 weeks so It's a short-term sacrifice I make to my enjoyment in order to get the benefits I'm looking for in the end. That's what I meant about how much cardio you do being dependent on your personal goals.
I'll give you some general rules of thumb:
* To begin an exercise routine, combine cardio and weights on the same training day, 3x per week (e.g 20-30mins each of cardio and strength training).
* To up the ante with a workout routine you already have, extend to 5x per week, either keeping the combo format or starting to split your sessions e.g mon/weds/fri weights, tue/thu cardio.
* To trim fat, ensure that you have at least 3 cardio-based sessions each week.
* To keep/gain lean muscle, ensure that you have at least 3 strength-building sessions each week (bodyweight workouts count).
* If you want to work on performance, combine cardio and weight training movements in the same routine 5x per week, ensuring that you incorporate balance training and mobility work as well.
Now, there is more to consider when building lean muscle is the goal - what body parts to work on each day, specific cardiovascular zones to stay within etc. but I think that's a topic all of it's own so I'll leave it for another post!
I hope this helps. If there are any questions that you have specific to your goals, let me know and I'll do my best to cut through the white noise for you. Subscribe and include the question and I'll get back to you!