The phosphagen system is also known as the ATP-PC system.
Adenosine triphosphate (ATP) is the energy currency of the body.
The "tri" in ATP suggests this molecule contains three phosphate atoms.
There is a high-energy atomic bond that keeps the phosphate atoms together in the molecule. When the phosphate is split off from the molecule causing ATP to become adenosine diphosphate (ADP), the energy released from that broken phosphate bond is used to power the contraction of the muscle fibre.
The creatine phosphate then sacrifices one of its phosphate atoms to ADP, thus converting it to ATP so that the cycle continues.
The ATP-PC mechanism is almost exclusively used during the first few seconds of exercise, irrespective of intensity, with energy coming from the breakdown of ATP stores within the muscles.
These ATP stores last only a few seconds, after which the PC breakdown provides power for an additional 5-8 seconds of operation.
This system can sustain maximum power for 10-15 seconds, but 1 second at peak power is all Nagisa needed.
The match should end in one second, less if Nagisa breaks the 10 m/s barrier. Yet, time went slowly.
Just as how Nagisa focused on hearing the start signal and reacted within 0.137 seconds, Nagisa was aware of every tenth of a second that stretched on.
In the instant, his feet touched the ground, lightning of nerve impulses coursed through his leg, causing them to contract and push off the ground.
The release of adrenaline sends more blood flow to his muscle and thus more oxygen allowing his muscles to work at an elevated level.
Although Nagisa was past his prime age, he should have been training to break the speed barrier a long time ago. He never let up on his training every day but every time he passed 9 m/s he would trigger a post-traumatic stress disorder and fall short.
However, when will he break through his PTSD? Another decade? No, he wasn't getting any younger. Any year now and it will be impossible for his age.
Tomorrow? That's what he tells himself every day. Then, when will he make a breakthrough?
Hikaru's youth and skill reminded him of his past self. He had forgotten something very important.
He used to fight like every day was his last. Furthermore, he could not wait another second. Nagisa had to rip every muscle fibre in his legs to the point he could no longer stand anymore. Then, they could rest and regrow the next day.
'Now! I'll surpass my limits even if it kills me!'
The mental blocks in his mind were broken, and his body's restrictions were lifted.
The last stride accelerated him past the finish line and this triggered the laser gate system.
Nagisa slowed to a stop.
Rather than being exhausted, it exhilarated him as he sprinted for a second. The excess energy vitalising his muscles. Nagisa still breathed hard because of the mental toll.
He looked at his daughter's pale face.
"So? How did I do?" He asked.
She was too stunned to answer him.
Without waiting for her, Nagisa went to her side and saw the two numbers he was looking for on the stopwatch.
The time he finished and his calculated speed.
0.976 s 10.24 m/s
He did it…
"Wind gauge?"
Before he celebrated himself silly, he had to check the tailwind. Again, he didn't wait for Chisato to answer.
It was practically windless tonight, and the rows of houses covered them from the wind.
0.3 m/s tailwind
Yes! The wind assistance is negligible, and he still would have been faster than 10 m/s without it.
A speed of 10.24 m/s easily broke past the ten-second barrier. If this was a 100 m race, then the time would have been 9.76 seconds.
Usain Bolt set the record at 9.58 seconds and 10.44 m/s so Nagisa did very well.
"I did it! Hahaha!"
Nagisa started jumping up and down and throwing his arms up.
Chisato was still confused.
Nagisa wasn't surprised as he knew she couldn't believe that he had finally succeeded. It was unexpected that it had happened tonight.
"Come on! Laugh, will you? We did it!"
"Dad…"
"Hikaru, how did you do?"
Nagisa knew that once he broke the 10 m/s mark that Hikaru wouldn't stand a chance, but he asked anyway because he was curious about how this talented young athlete fared against him.
At most, the kid could break past and get 10.1 m/s. That was how highly he thought of the young man.
He pressed the forward button on the stopwatch, but it didn't go to the next page.
"He… Hikaru won, dad…."
"Hm?" Nagisa responded automatically without paying attention to what was actually said.
He thought the stopwatch was having problems because Hikaru's data should pop up next. He then pressed the back button and saw some numbers.
0.742 s 13.48 m/s
"Huh?" Nagisa said, unable to process what he was seeing.
The numbers appeared so clear but a strange hidden weight was revealing itself on his head. It was like a blood clot had suddenly lodged itself shut into a blood vessel. His vision got blurry, and he was extremely confused.
Was the machine broken?
How could it be? He did maintenance every day and the laser timer system is advanced and accurate. They also used it in the Olympic 100 m sprints, although they used a superior camera.
Nagisa replayed the video recorded in the camera capable of 100 frames per second. A small white icon with a gun and a muzzle flash appeared on the video showing that the starting gun was fired.
He saw Hikaru react much faster than himself and when he passed the first laser gate, a small white icon of a leg and dust smoke replaced the gun icon. The timer for the race started.
Hikaru was moving a couple of frames ahead, leaving Nagisa behind and finishing early.
If it wasn't for this footage, Nagisa wouldn't have believed it.
'What the hell did I just see!'