ATP (Adenosine-Tri-Phosphate) supplements are over-the-counter products sold with the intent (of questionable honesty) to increase the reserves of ATP in the muscles by promoting sports performance.
It seems that the density of ATP is depleted by intense physical exercise and that its TOTAL recovery requires a maximum time of 3 days (physiological cellular synthesis).
Do D-ribose supplements really facilitate the restoration of ATP stores?
Let's say that even if it were possible, the "effect of" D-ribose supplementation would not boast any notable ergogenic effects on performance; let's see why:
simplifying, let's say that the "reserves" of ATP represent an energetic substrate "potentially" usable in muscle contraction. The first consideration concerns the actual importance of this substrate; from the QUANTITATIVE point of view, it is SO SMALL that it has an absolutely negligible metabolic role and is (in my opinion) useless.
Furthermore, most readers will be reflecting on the fact that, in common sports physiology texts, the 1st energy substrate of muscle contraction is always cited as the 1st energy substrate of muscle contraction. creatin-P (CP), also known to be the quickest to run out; glucose and fatty acids follow. In fact, users don't make any conceptual mistakes! From the physiological-sporting point of view, the reserves of ATP are considered so insignificant that they do not deserve to be placed inside the energy mechanisms, also because it is not a real substrate, but rather a reserve of the molecules that LEAVE energy BUT they do not produce it.
Why do ATP supplements contain ribose?
The so-called "ATP" supplements contain mainly ribose and, at best, few vitamins; ribose is a glycide / sugar / carbohydrate / carbohydrate (if you prefer) with 5 carbon atoms, so pentose. Ribose, in addition to constituting an essential element of nucleic acids (genetic heritage), in association with "adenine and three molecules of phosphoric acid, represents an essential piece of the ATP molecule; ... so far everything is clear.
Instead, what IS NOT "CLEAR is:
"Why should the" increase in ATP "be ergogenic, given that the sites in which the ATPs are located have a specific and NOT modifiable number?"
Certainly as a result of physical exercise the depletion of ATP reserves occurs, but this depends on the level of athletic training, the subjective capacity for recovery and the intensity of the performance. If ATP were truly a limiting aspect, some athletes could NEVER train 2 or even 1 time per day.
... Furthermore...
"Why should having more ATP molecules increase performance, since it is a perfectly RECHARGEABLE molecule?"
In fact, ATP is a molecule located in the head of the myosin ", one of the main proteins responsible for muscle contraction; therefore, each myosin corresponds to a determined number of ATP equivalent to the number of its heads. It follows that, despite having more ATP molecules in reserve form, the muscle would not be able to use them unless after the "simultaneous annihilation of all the ATP present in the myosin heads (at least remote eventuality); for depletions physiological or sport-induced, the endogenous muscle stocks are sufficient.
Furthermore, ATP is a rechargeable molecule (as if it were a battery); following muscle contraction it becomes ADP or, more rarely, AMP. In muscle contraction, ATP loses a group (or two) of phosphoric acid; but the latter, through the 3 energetic metabolisms (anaerobic alactacid, anaerobic lactacid and aerobic) and by the intervention of the enzyme ATP-synthase, is promptly reconnected to the original molecule restoring the functioning of the complete ATP.
In conclusion, what would additional ATP stocks be used for? Probably to ensure a good business profit for traders!
Curiosity: difference between ribose and D-ribose
The wording D-of ribose simply indicates its isomeric form, that is the different distribution in space of the atoms within the SAME molecule; for amino acids, for example, the opposite of the D- form is the L- form, easily identifiable (with the appropriate means) by viewing the rotation of the plane of polarized light which, in the two isomers, is completely opposite. If in the molecules of the organism there are optically active compounds, therefore differentiable in D- and L-, they will never be interchangeable; just as in human proteins the amino acids are always in the -L form, in the nucleic acids and in the ATP the ribose it is always D-ribose. This explains why ribose is named as in ATP supplements D-ribose and not simply ribose.