Energy systems = Fat Oxidation I Anaerobic Glycolysis I Creatine phosphate (& stored ATP)
Let us understand this complicated science which looks simple but trust me it is not from what I have observed in the sports world. The thrust on protein or high carbs diet; the frequent use of energy drinks; and the belief on fat proves that not many have understood it in depth.
Ques: Which energy system do you think we use most in sports like Cricket, Baseball, Hockey, Badminton, Tennis, Kabbadi etc.?
Ans: ALL….
Ques: Which energy system is most important for above sports?
Ans: ALL…
Ques: HOW?
Good question….let us understand it:
Fat oxidation: Almost everything we do through out the day, on the field/court, or any effort where you are not exhausting yourself to the max. Think of a Car with 4 gears:
Gear 1: Stored energy in the system + circulating energy which comes from food you have ingested before exercising. Say the fuel which is in transit from the fuel tank to engine.
Gear 2: Stored fat for any sub maximal effort (lasts all day) – YOU will be surprised to know how we can improve this. Read on…
Gear 3: Glycolysis – Glucose/Carbs used as a fuel stored as muscle glycogen (storage form of glucose) – lasts a few seconds
Gear 4: Top speed – top effort – maximal output that you can generate (Creatine Phosphate) – again, lasts a few seconds. Such is been my knowledge until this. However, I have been corrected by an expert on this explaining PCr generation is happening constantly as a by product of oxidative and glycolytic pathways.
Sports: Think of a car navigating in any big town like ‘Delhi or Mumbai’ in peak office hours. It stays on FIRST Gear…shifts to Second Gear…then for a few seconds it can shift to Gear 3 & 4 but comes back to Gear 2 and stays there 🙂
Ques: How do you think we can improve the performance of a car (assuming we can work on RPM and thereby improve ‘gears’ performance)?
Ans: By running the car in Gear 2 efficiently
Gear 2 = Fat oxidation (mitochondria health)
A sprinter moves from Gear 1 to Gear 4 in few seconds but a marathon runner has to maintain a constant speed for a very long time and therefore stay on fat oxidation for maximum time. They inadvertently use all energy systems but their dependence is most on ‘Fat oxidation’.
Imagine this – our sprint speed where we are running in 4th Gear is actually Gear 2 for a marathon runner? And this is where any average runner will get exhausted (lactate threshold – muscles are unable to process the lactate produced as a by product of glycolytic pathway) in say 15 to 20 minutes; a marathon runner goes on with same speed for 2 hours plus. What makes them so efficient?
- Their 2nd Gear performance matches anybody’s 4th Gear performance. And this is only possible when I can drive the car to better/more speed in Gear 2 and sustain it for longer time.
- Secondly their ability to process ‘Lactate’ – byproduct of Anaerobic metabolism directly as a fuel via cytoplasm of muscle cell (not only via Cory cycle which takes longer time). Imagine if by-product of your fuel also starts getting consumed as fuel then you are talking about a long sustaining machinery.
There is too much to talk about however I will try to keep it simple to help everybody understand this and drive home my point. Just how a gear’s capacity runs out when we increase speed; we shift our metabolism when energy (ATP) demand increases.
Science does seem to suggest that it is the energy demand that drives the metabolic pathways even though they are imbibed into each other and all work simultaneously.
IF we are training regularly (sportsmen) and eating our regular food then we do not have to worry about the fuel for ‘Gear 3’ or ‘Gear 4’ (from nutritional perspective) because we keep our glycogen stores full. We have a capacity to store glycogen so we don’t need to focus from nutritional perspective. Instead our focus should be more on maximising fat oxidation threshold. Surprised? Read on….
With regard to sports like badminton, tennis, hockey, basketball, cricket, baseball; it does seem that one would use more fat than carbs provided they have trained well at ‘Gear 2’ level and thereby enhanced our mitochondrial capacity. And using more fat does not necessarily mean eating more fat. Carbs also get converted into fat and we are never short of this fuel.
The key is in utilizing the energy optimally depending on how far you have to go – endurance.
Imagine yourself on the field all day and you have to perform at your best towards the end of the day. Who do you think will have more energy to perform:
a) Somebody who shifts from Gear 2 to Gear 3 frequently all through the day depleting their glycogen stores? And even though they may be repleting glycogen stores but constant threshold will deplete the stores faster.
or
b) Somebody who has build capacity to push in Gear 2? Who doesn’t shift from fat oxidation to glycolysis frequently and instead handles most of their running around on fat oxidation preserving and keeping glycogen stores for sudden bursts?
You are right….my answer is also (b).
Analogy: You can drive your car up to say 80km/hour in 2nd gear Vs a car where your max speed in 2nd gear is only 40 km/hour. Which car will speed up faster in 3rd and 4th gear?
Ques: What brought me to this subject?
Ans: I was always intrigued by how my players consistently lost weight (through different assignments) besides hogging on a hotel buffet. Whenever I looked at their plate, I always wondered how could they eat so many calories and still lose weight. This brought me to dive deeper into my training and what it does that they manage to burn all the calories they eat + additional calories, creating a calorie deficit and lose weight.
My conclusion:
I mostly trained my athletes in a way that improves their fat oxidation (Gear 2). Gear 3 & 4 comes automatically into play just like how gears shift in an automatic car as we paddle hard or say they are working simultaneously with minimal load. This is in contrast to what sportsmen do in the gym where they are using ‘Gear 3’ & ‘Gear 4’ energy systems maximally and less of fat oxidation. The scenario gets reversed even though all systems are working.
I can’t think of any other reason on how they created calorie deficit by eating a wholesome diet.
Understand the difference because it is most important: When we train at the gym and lift weights…we are not making our performance in ‘Gear 2 – fat oxidation’ improve and instead, inadvertently, we work on ‘Gear 3 & 4’.
Example: This is why cricketers struggled to lose weight before or during IPL. How do we lose weight if we are not burning fat? It should NOT be that difficult to lose weight considering the effort our players put in practice and training? Like I said above…we use all energy systems in sports however we have to improve fat oxidation/mitochondrial health to put it to better use.
Ques: How do you lose weight?
Ans: When you lose fat 🙂
Ques: Does that mean we don’t lose fat via weight training?
Ans: NO…but to lose fat via gym training, we have to train heavy consistently to burn extra calories (create calorie deficit) which is not possible when you are in sports. Instead what players mostly end up doing is working on the glycolytic (gear 3 & 4) and burn minimal fat. To add to this players ingest extra protein in the form of supplements which does nothing but to get converted in ‘Glucose’ or ‘Fat’ because of the amount of damage we do to our muscles do not require extra protein. Ideally, we should swap calories if we are adding protein supplement unless your muscle damage is significant enough to consume all the protein + calories you ingest via your food. You can read my article on ‘Protein’ if you need more clarity on the subject. Protein is excellent but we must understand how to swap it if we were to lose weight.
Ques: What do we require to lose weight?
Ans:
a) Calorie deficit – in simple terms, your energy burn should be more than energy (food/calories) we eat.
b) Improving our fat oxidation – burning more calories – creating calorie deficit

Conclusion: If one has to lose weight then they must train in a way that improves their fat oxidation while training for the sport they play. Otherwise they will lose weight via diet BUT gain again. Again lose weight and gain weight again….the saga will continue! But if you repair your metabolic machinery by incorporating training that burns and improves your fat oxidation, you don’t need to worry about gaining weight again. Because once an engine is rewound; it must work fine without having to worry about any issues.
If you are a scientist or a nutrition expert then please feel free to question any of the above by bringing your science forward. This is how I have understood science by sweating it out both in the gym and on the field and I will be happy to learn more should you have anything to add or discount. This conclusion is from live case studies of 5 months seasons.
My effort here is to make players/coaches/non-experts understand the mystery behind not losing fat!
Umesh Chhikara