When starting a cut should I use 40/40/20 until I start to plateau and switch to a carb cycle approach? Morning cardio.. how long and hard? (should i up this time or lower cals when beginning to plateau??) and 2-3 hiit sessions how long?
Doug, Is this the first time you've cut? I ask because the question that you posted are different ends of the spectrum. There is no real secret to dieting but there are a ton of ways to approach it. First thing I would do is calculate your BMR to find out how many cals it takes to maintain the current level of body compostion that you are currently at.
The next order of business is gauge how you personaly handle macro's. Are you one who can handle more carbs and still lose fat? Are you a keto guy? (high protein , high fat). Once you decide this, you can begin to tweak the BMR calorie calculation and fit the macro grams to hit the numbers. The rule of thumb is to ingest at least a gram of protein per lb(lean) of body weight. Some guys go anywhere from 1.5 to 2 grams per lb. In the case you would obviously have less room and would adjust the other macros (carbs, fat) to hit the BMR number.
Once you have this down you can adjust the the carb or fat grams down to suit your fat loss needs. Remember, if you are cutting, the purpose of the protein is to maintain muscle in the absence you carbohydrates. There are ways to manipulate that scenario of course, but it is best to start with the basics. Again, these are broad statements.
Cardio wise, it is best to complement it to the weight training that you are doing. A good idea would be to mix steady state with a few interval sessions a week. Here again, you do not want to take the kitchen sink approach. Start slow, maybe do a couple steady state sessions after weight training or fasted in the morning, and do a HIT session on the off days. If you do everything at once you have no where to go when you plateau- add more cardio in gradually.
People tend to forget nothing is independent in terms of fat loss. Weight training should be in check first, diet should support the training and cardio should complement the other two. Always remember it will depend on what works for you. Hope this helps.