It’s been 4 years since I took the plunge & decided to transform my health. Initially, when I subscribed to a gym & started working out, there was no one to guide me on correct workout out schedule. With the objective of shedding 35 kgs, I started doing cardio for 45 minutes to an hour along with 25 to 30 minutes of weight training every day. I followed this schedule for 3 months & I was able to shed around 7 kgs. However, I was not able to observe any changes in my strength & endurance level. Besides, there was no visible changes in my muscles. I could only boast of calories burnt. However, after doing a lot of research & interacting with fitness enthusiasts in my social circle, I was able to figure out that cardio alone would not help you burn that stubborn fat.
So what does this mean? Is cardio not beneficial for weight loss & fat loss? What should be duration & intensity of cardio? What strategy should we adopt if workout in the evening?
Cardio no doubt helps you burn calories & create that calorie deficit by burning more calories than you consume during the day. So what is the impact of cardio on overall body composition? If are doing cardio for longer duration of time, body does burn some fats but it also starts breaking muscles which will be converted into glucose which will be used as energy by the body. This loss in muscles will further reduce your metabolism since your muscles burn energy & with burning of muscles, less energy will be expended. So why does this happen? Here comes your Villain: Cortisol Hormone. When you indulge in standalone & low intensity cardio such as treadmill or elliptical, your cortisol level becomes high. Cortisol is a stress hormone which breaks down your muscle when you do cardio in isolation
So what is low intensity cardio? Low intensity cardio is doing jogging/brisk walking at moderate speed for a longer period of time. High intense cardio is when you run at high speed & when you take small intervals in between it becomes interval cardio.
Ideally, if you want to burn your fat, do cardio empty stomach in the morning followed by weight training since when you are empty stomach, your fat cells are not engaged & you are in fat burning stage. Cardio should not exceed 10 minutes.
So what should be correct workout strategy?
- Combining weight training with low intensity steady cardio state: Steady cardio helps you create calorie deficit & burn that extra fat & weight training makes sure that your maintain &/or build muscle.
- High intensity interval training(HIIT): When you dow low intensity cardio, you start breathing faster since you need more energy to carry on the workout. Your body derives this energy by sending oxygen to muscles, making muscles to break down into glucose to provide you the energy. However when you do HIIT, your body needs energy faster & it cannot wait for oxygen. Body as such increases level of lactate. The glucose is converted into lactate which is sent to the liver which is used to be converted again to glucose to be used as energy. You must be wondering so why does HIIT leads to fat loss since in LISS as well glucose is used to generate energy? However , HIIT not only increases your Cortisol levels but also your growth hormones & testosterone level. Besides HIIT also prevents you from overtraining since as your lactate level goes up, your muscles ability to go on for some more time goes down. Lactate has an upper limit. HIIT goes over that Lactate level when we are running at a high pace. Even when we stop or start walking suddenly, our brain is under the impression that lactate levels are over the top Therefore ability of our muscles to continue goes down
