FOR FAT LOSS - WALKING OR RUNNING - WHICH IS BETTER ?

                                 

FOR FAT LOSS - WALKING OR RUNNING - WHICH IS BETTER ?

For maximum fat loss which is better Running or Walking ? Both running and walking are great for burning calories , but in this blog myself will try to explain all the reasons why they work & don't. Also find out if you should run or not.

Every year millions of people resolve to lose weight , but every year millions of people gain the weight back, is that because they did something wrong or because they are lacking in character & will power. Lot of people believe in the notion of "no pain - no gain", but is that really how it works for weight loss & fat burning.

The idea of  losing weight & burning fat based on exercise like walking or running is based on the idea that we have to expend energy or use up calories , some of that calorie is stored as fat , so if we expend more energy then we will burn lot of fat, that makes sense, but it is not as simple as that. First let us look into where the energy come from & how is it different if we are running or walking .

The 2 ways the body makes energy are : 

1) OXIDATIVE PHOSPHORYLATION, which simply means we are making energy in the presence of oxygen, that is we have enough oxygen supplied that we can send the fuel to MITOCHONDRIA which uses oxygen to oxidise the fuel, this fuel could be fat or glucose. If we have enough oxygen then we can make energy / fuel called ATP (Adenosine Triphosphate) it's actually the currency of energy in the cell, we can make 38 units of ATP from one unit of glucose, but fat is a larger molecule so we make more than 38 ATPs. The important part is, it is a very efficient way of making energy  & in the presence of oxygen we can make a lot of it & all of that oxidation is happening in the mitochondria. As this is an efficient way of making energy, so our body prefers this, because at rest & a moderate level of exercise the body prefers to use Oxidative Phosphorylation and prefers to use fat for fuel. At rest & moderate level of exercise we use about 85% of the energy from fat & 15% from glucose, but both of these fuel sources are channeled in to the Mitochondria for the use of oxygen to make ATP. 

2) The alternative way of making energy is known as GLYCOLYSIS, meaning splitting sugars or glucose. When there is shortage of oxygen in our body then the body relies on Glycolysis, this does not happen in Mitochondria, it is a separate mechanism, this happens in the cell in the cytoplasm, but outside the mitochondria, this is not efficient at all, as we can make only 2 ATPs from one unit of glucose. 

So, when we have oxygen then we can make 19 times more energy (ATP) than when we do not have sufficient oxygen. This means that GLYCOLYSIS is an emergency way of making energy. This is important when we have crisis ie., when we do not have oxygen or when we have to make a sprint during emergency or when we have to escape from something, then we have a backup method of making energy but it is very inefficient , it costs us to make certain amount of fuel and have to use up a lot of glucose, 100% of this mechanism of Glycolysis comes from glucose, it dose not work for fat.

So, if you plan to run or walk in order to lose weight or fat then you need to understand that which of these 2 mechanism works in running & walking & whats the balance. There is something called AEROBIC metabolism that means with air. When you are walking with an intensity where you are below 120 beats per minute of heart rate, because at that heart rate for most people you are going to be breathing normally , not going to be huffing & puffing , you will be taking deep breaths with a steady rate, this means you will have enough oxygen to provide Mitochondria to stay with OXIDATIVE PHOSPHORYLATION, without needing to start in to splitting sugar. Thus the Aerobic metabolism or the aerobic exercise which is all activity where there is less intensity & not huffing & puffing, you will burn the fast maturity of your fuel from fat , especially if you are fat adapted , then there will about 85% burn from fat & 15% burn from glucose, but this glucose is still going to mitochondria for oxidation. If you increase your intensity little bit then the glucose % will go up slightly but still stay in the oxidative phosphorylation. As you further increase your intensity and cross over to ANAEROBIC (heart rate comes to 140-160 beats per minute) and you start huffing & puffing for more air now there is no longer enough oxygen to provide mitochondria with enough oxygen to maintain OXIDATIVE PHOSPHORYLATION, so now the body can not rely on this & will start breaking down glucose & start the Glycolysis mechanism & using lot of carbohydrate rather quickly.

Thus we can see that , if you are fat adapted & are doing Aerobic then you are in the fast majority of fuel provided from fat , but as you start Anaerobic then the glucose becomes dominant, the intensity will determine how dominant it becomes, more huffing & puffing means more use of glucose , carbohydrate than fat.

A lot of people think that it is just about calories, "if i burn more calories, run more faster then i will burn more fat", but that's not how it works, the only way to burn fat is with oxygen which is possible in the OXIDATIVE PHOSPHORYLATION , you can only burn fat up to the Aerobic threshold then the mechanism adds by shift to GLYCOLYSIS where you burn glucose.

If you wanting to burn that fat and keep that going for hours , then you can go for walk for hours or a leisurely bicycle ride for hours if you are fit and capable , but if you are running and huffing & puffing then we can not keep that up for too long, may be maximum 20-45 minutes depending on how fit you are. So, in walking where you can go for long duration then you can burn lot of fat. In running you will be burning calories but the calories wont be coming from fat as oxygen sets the limit. When we go from Aerobic to Anaerobic then the body shifts from a peaceful to emergency state, thus switching to using the reserve pathway, thus using of glucose and glycogin quickly. As in Glycolysis more carbohydrate is used & look for other carbs, because of the cortisol which is released during high intensity routine, we become carb adopted ,burning more carbs , not fat. So, as we burn through the carb stores, we get hungry and get cravings.

In Aerobic - walking you will not have any extra hunger, where as after running where you go through burning of carbs, after an hour you will probably be ravishing . When we run we trigger cortisol and thus increase in blood sugar and insulin . Insulin we know is a fat storing hormone,  when you run you become hungry and consume more carbs & insulin converts carbs into fat. Every thing about fat burning is about resisting insulin & insulin resistance. Low intensity aerobic exercise is pure fat burning and stays stable till we trigger cortisol.

While we are running we will be burning more calories per unit of time but it dose not really mater as we cannot keep it for long so the total calorie expenditure is not higher, because we are triggering cortisol , you will be more hungry, suppose you have the will power to resist that hunger and do not eat, then what happens is your body has used all the glucose, then the body will try to find the source and have to break down muscles and that is obviously not that you want. 

So between walking vs running , for maximum weight loss, the clear winner is walking. 

However, dose that mean you should never run ? & should always walk as the only exercise ? Of course not, then who should run or what type of person should run - someone who is fit regardless of age, lean, you should be insulin sensitive, you enjoy variety, then can run once in a while, but not regularly. Do not think you will be more healthier if you run or burn more fat if you run. Should do more of your activity AEROBIC.

Who should walk ? If you are already over weight, that means you are pretty much insulin resistant and you are not super fit & your body is not ready for the stress, then should always walk. If your primary motive is health then walking is best for most people. Walking also reduces the risk of high blood pressure, cardiovascular disease , stroke & dementia.