25/03/2024
Okay my Friends,
Let's continue our last topic of doing two training sessions twice a day.
This theme is very controversial, as opinions are split into two poles - some insist in favor, while others argue otherwise.
One says, by doing training twice a day, you actually build and strengthen your muscles over time and get stronger faster.
Others say it is just a waste of time and there is a high risk of being overtrained.
Well, both sides are partially right. Let's figure it out.
Before that, let's briefly recap our intensities zones, how many they are (Z1-Z7) and what are they for?
Z1 - Active recovery: very low-level exercise such as walking, hiking, or easy spinning. The energy source is pure fatty oxidation. Duration could be all day; just keep in mind hydration and eating on time.
Therefore, it doesn't make sense to do training twice in a day.
Z2 - Endurance: Producing the capillary system, development and enhancing the ability of the body to absorb oxygen by the bloodstream in the lungs, being then transported to the cells. Aerobic Capacity.
The energy source Glycogen + Fatty Acid.
Duration up to 4 hours, recovery time after exercise takes up to 10 hours.
Hence, it doesn't make sense to do training twice in a day.
Z3 - Tempo: Low tempo pace continues producing the capillary system.
Mid and High tempo paces increase mitochondria density and division within muscle fibers (muscle phosphorylation).
The energy source is Glycogen and Fatty acids.
The power output increases, and the share of participation in Fat Oxidation decreases, with glycogen stored in muscle playing a more significant role.
Recovery time 10-16 hours.
This leads to the development and enhancement of the oxygen cascade.
Though glycogen doesn't deplete fully in muscles and still remains, it makes sense to consider splitting the workload into morning and evening sessions, especially if you are a pro-rider and in the preseason volume-load stage.
Z4 - Anaerobic Threshold (AnT): This is the conversion rate of glycolytic Fast-Twitch muscle fibers (Type IIa) into glycolytic oxidative tissue. This zone is most important in endurance sports because it allows you to maintain a well-balanced ratio of power and time. Just imagine, well-trained athletes can sustain a workload of 95% of maximum heart effort for up to 90 minutes.
To clean 4-6mmol/L blood lactate concentration takes 14-20 hours, recovery time.
The energy source is Glycogen.
Here is also a point to think about to split your workload to a few training sessions.
However, I'm not enthusiastic to do that in these zones (Z3-Z4).
Okay, we reached Zones 5 and 6 and here are interesting things in our aspect.
Before that, one remark please.
The energy that drives us forward (contracts our muscles) is ATP and ADP. The direct source of these energy is glucose, the second most far source for these energy is glycogen, next carbohydrates, protein and at the end as a clean fuel is fat.
Actually there are more complex processes and I don't want to be deep in a Krebs cycle (citric acid cycle), so I just try to simplify things.
So, one molecule of sugar (glucose) gives us under aerobic respiration 38 molecules of ATP and under anaerobic respiration only 2 molecules of ATP.
Although Aerobic zones as energy source more efficient, but produce less power output as Anaerobic zones.
Aforementioned under aerobic zones our body uses fat, carbohydrates, protein and glycogen as energy sources for producing ATP.
To break down one molecule of these sources takes time, and sometimes we have to perform explosively, as in the "Fight or Flight" response.
In such cases, the aerobic zones cannot provide a sufficient amount of ATP in such a short period of time to maintain such a high power output. Thus, anaerobic zones come into play, which produce huge power output but also consume a large amount of glucose molecules.
Don't forget that the source of glucose and glycogen in our body is strictly limited, and our brain alone needs to reserve for itself at least 20% of the total amount.
In other words, glucose in our body serves as a trigger to supply instant fuel to meet sudden demands.
Okay my friends, I see this post has become too long and apparently just few will come to this line.🤣
I want to make a break here and in a next post I will continue this topic at zones Z5-Z7.
Stay tuned!
