Keto is going to deplete you of muscle glycogen . you'll have more cardiovascular endurance and energy from being in ketosis, but you'll have less strength and ability to perform reps to and beyond failure like you would normally be able to. so you can keep your training the same as its been, just know your reps will go down and so will your strength . however cardio will be easy as fuck.
the traditional Keto diet is a HIGH FAT DIET . your body is becoming 'fat adapted' , you run off of dietary fat and stored fat , you no longer run off carbs and glucose.
40g of fat on a keto diet is NOT a keto diet. heck the govt. and the American heart association recommend more fat then that just on a normal persons diet , let alone someone on Keto.
70% of your diet needs to be from fat, 25% from protein, 5% trace carbs from veggies.. so if you eat 3000 calories per day. then 70% of those calories should be from fat . thats 233 grams of fat per day.
sounds nuts right, that much fat? well thats what traditional Keto is.