Eat more and stop doing cardio. If your goal is fat loss resistance training (weight training) is by far the best tool to use for long-term weight loss. If your goal is short-term fat loss, go ahead and give your best Usain Bolt impression on the treadmill and supermodel impersonation at the dinner table.
Once you have worn yourself out enough, both mentally and physically, you will have nearly destroyed your metabolism and maybe even gained more weight than what you were unhappy with in the first place.
Running on the treadmill religiously will definitely slow down your metabolism. Cardio does burn more calories than any other exercise by far, but the issue with cardio is that it signals to the metabolism that your body needs endurance to survive and less strength. The body therefore becomes more efficient with the calories digested and less efficient toward building muscle. This makes it even harder to lose weight after becoming dependent on cardio for weight loss. Your body is adapting to a new environment that you’re putting it in, which makes the body better suited toward running faster and longer.
It is no surprise that professional athletes are subject to an even stronger risk of obesity after retirement. Cardio is a logical way to lose weight in a short amount of time in case you have a pool party to attend next week and your crush is going to be there. But if that is not your situation, stay off the treadmill.
Restricting your calories to a low number will also slow down your metabolism a lot. When you scarcely eat, your metabolism is again adjusting to this new environment. After a while your body will adapt to the new number of calories you are feeding yourself in order for you to survive.
This is how hunters and gatherers were able to survive after long droughts without catching their next meal. In order to survive, your metabolism will do the same to a lesser extent. Depending on how low you restrict your calories, you will gain weight if you eat over the caloric total you set while restricting, which in extreme cases can get very low, ultimately making it hard to live healthily while eating such little food. Some people become anorexic and create severe metabolic damage.
Ways to boost your metabolism are to lift weights and slowly increase your caloric intake. One pound of muscle can burn up to 11 calories a day. If you add a pound of muscle your basal metabolic rate, or calories you burn while in a resting state, will go up.
Going through a long period of a slight caloric surplus can get your metabolism used to a higher amount of calories in its system, making it easier to lose weight in the summer when you decide to go into a caloric deficit or eat at maintenance. Find your maintenance calories and create a caloric surplus or deficit depending on your goal.
Some bonus tips include walking and eating correctly. Walking is a much better option to
burn calories if summer is coming up. It is much more realistic to be consistent with, and it will not damage your metabolism nearly as much as running would. Nutrition is important to focus on. Hit your macronutrient goals and eat plenty of protein. Protein helps build muscle quicker and muscle burns calories.
Hopefully you are not receiving this information right before summer, but if you are reading this during the fall or winter, do take advantage of the science-based facts and hit the gym.