Your body loves you just the way you are; homeostasis is the name of the game. Unlike everyone you have ever dated, your body wants you to stay exactly the same, and has set up a lot of measures to keep you from physically changing in any way. Knowing this, it would only make sense that whatever we are going to do in order to elicit a change is going to have to be discrete enough so that the body doesn’t notice. Just like every relationship you have been in, you are going to have to do everything behind your partner’s back, or else you are gonna get in trouble.
Any major decrease in calories, restriction of a macronutrient, or increase in energy expenditure over an extended period of time will cause the body to go into a type of starvation mode, in which it makes self-preservation a priority. This means that excess muscle becomes a luxury, not a necessity, and metabolic rate will be slowed down to maintain homeostasis. Basically, your muscle is more likely to become food, and your newly-slowed metabolism means you now have to cut calories even further to keep fat loss going. It is very important to take into consideration the effect dietary restrictions have on metabolic and anabolic hormone levels. To make a long story short, long term hypocaloric diets decrease most of the fat loss friendly hormones that you should be looking to increase and take advantage of. As you can see, this can become a vicious cycle, and may be the reason for all the stupidity with competitors on extreme restriction diets coupled with hours of cardio every day.
Before we go on, I have to note that all of my opinions on cardio are based on a model that has proper nutrition and some type of intense resistance training in play. Solid nutrition and heavy weight training will never be outdone or replaced by cardio. For my examples I am going to refer to low days from a carb rotation template made popular by Justin Harris. The carb rotation type diet is excellent for keeping the metabolism stoked, and the body unaware of the slight changes that can be made. Another reason I am using a carb rotation diet as the example is—you guessed right—it pairs up perfectly with cardio cycling. I tend to schedule cardio on the low carb/lower calorie days (and medium days if necessary).
For every proponent of High Intensity Interval Training (HIIT), there is someone else screaming that steady state rocks way harder, and two others scoffing that cardio is stupid and you shouldn’t do it. I agree. Using a blend of HIIT, Low Intensity Steady State (LISS) cardio, and taking breaks from cardio altogether, you can create a great environment for fat loss, not send your body into a state of panic, and get lean without losing all that hard earned mass on your legs. Ahem, sorry. Your biceps.
Add cardio at the bare minimum to produce results when you’re first starting. Slowly adding to allows for small increases as the prep goes on.
Make the Most of Your Diet
Do your cardio on lower calorie or lower carbohydrate days. Combining cardio with lower calorie days to help get your body into a caloric deficit. If your metabolism is humming right along, then these deficit days will be very effective at burning off those love handles. Try to maintain an overall calorie intake that is close to isocaloric, with lower carb/calorie days sprinkled in during the cardio intensive weeks. Long term hypocaloric diets have been shown to decrease many of the hormones that are beneficial to fat loss.
High intensity resistance training with cardio intervals of short bursts under 3 minutes is more effective in fat burning and maintaining hormone levels better than staying on a treadmill or in a stuffy spinning room for an hour!!