I've got a confession to make…
In the year 2006, I've seen so many articles on cardio that it even made me confused! Everything from don't with it "good night to cardio" to cardio is worthless to HIIT training and all kinds of crazy ideas. There's anti-cardio gurus and cardio masters.
At times, cardio seems like a diet plan.
Let me explain that…
With a diet, you have so many foods to choose from that you can literally make any combination up and call it a "diet."
Cardio seems to be that way lately. There's a lot you can do with your cardio workouts. Keep them short, make them intense, do all kinds of machines, do it every day, do it once a week, don't use machines at all but go outside and run hills… etc. List goes on and on.
Let's try and answer the question of the best time to do cardio and how much recovery after your weight sessions you need in order to get workout but without burning up any precious muscle.
3 Simple Steps to Effective Cardio Workouts
1- Use cardio as a tool.
Cardiovascular exercise is good for the heart. However, so is weight training. And lifting weights and building muscle will do more to get you leaner than 6 spin classes 6 times a week.
If your goal is to build muscle and gain weight or burn off the fat, then use cardio sparingly as a way to your goal.
Did you know that 1 lb of muscle burns more calories than 1 lb of fat? By focusing on building more muscle, you'll get leaner quicker than if you plug away at a treadmill all day long.
Let's put it this way…
If you cut bread with a saw (weight training) it gets the job done nicely. But if you cut the bread with a saw and then use a finely sharpened knife to make the slides perfect (cardio) you'll get the best of both worlds.
You'll get slides of bread quickly (saw) and you'll get them neatly carved out (knife).
If you can think of cardio as a tool to stripping off unwanted fat AFTER your weight training and nutrition is in order, you'll use the tool as it's meant to be used.
There's a loaded question if I ever saw one!
a) the right time is anytime it works for you. If you read several articles about morning cardio and you simply cannot do it, then do it when you can. There's plenty of studies that debate the optimal time to do cardio but they all point to the single fact that it doesn't make a massive difference in your overall gains. When it comes to eliminating body fat. Whether it's early morning, late evening, the most important thing is that you just do it.
b) do your cardio AFTER your weight workouts. Why after? Because your weight training workouts require something called glycogen. That's short term fuel. If you burn off and use up your short term fuel first, you'll have little to give when it comes to your muscles.
The fuel your muscles need for a weight training workout is different from the potential fuel sources you can use when doing cardiovascular activities.
When you do your cardio AFTER your weight training sessions, you are warmed up and have a better chance at using fat as a fuel source over glycogen.
3- Separate your cardio from your weight training sessions
If at all possible, try and give yourself plenty of time between a cardio workout and a weight session. Some programs recommend 8 hours. This means you'll do cardio in the AM and weights in the PM. You'll have plenty of time for post-workout nutrition and a few meals in there as well to help with recovery.
But what if you can't?
2 Tips to Cardio Workouts
Tip #1 – Do your cardio AFTER your weight session as in the step above. While this won't be ideal, it allows your body to use glycogen for short term fuel for the weights and potentially fat as a fuel source.
Tip #2 – Engage in post-workout nutrition (protein and carbs) after your weight training session. While you probably won't burn as much fat, you won't risk burning off as much muscle either.
The reason your body burns muscle is that it costs a lot to maintain it (metabolically speaking). In that case, make sure you can support the muscle by not overtraining and engaging in proper nutrition.
Those two simple concepts will go a long way in helping you to preserve muscle when you have a short rest period between a weight training session and a cardiovascular workout.
The bottom line is that cardiovascular exercise is part of a health and fitness routine. It should be used as a tool. Sometimes more (getting ready for a competition) and sometimes less (lean bulking). Lately it's been over-rated but it certainly isn't worthless.
Source 4 Foods Never To Eat