Saiyans gaining power after every battle and Piccolo

[Evil Vegeta]

Vegeta: “Fuhahaha…! We Saiyans grow stronger each time we fight…! The stronger the opponent, the stronger we become…So I’m becoming stronger too…! I almost died on Earth, and have now vastly powered up…!”

Freeza: “It seems that the Saiyans really do hide bottomless battle power…It increases greatly the more they battle…Of course, there’s no way they could be a match for me, but if I don’t think of the future and nip them in the bud now…After all, it’d be troublesome if they were able to become Super Saiyans…”

Vegeta says Saiyans grow stronger after every battle and that the increase is higher if the opponent is stronger. The Zenkai he mentions afterwards seems to be differentiated from the standard idea of Saiyans improving after every fight. The way it's said, simply fighting and winning a difficult battle will allow the Saiyans to become more powerful. Freeza basically echoes what Vegeta said.

So the question is: can you think of any points during Z where this took place? Seems like the Saiyans improvement only came from training or healing. I can't think of any instances where simply fighting a battle allowed a Saiyan to become stronger.

Vegeta: “Zarbon…Weren’t you supposed to know a lot about Saiyans? It wasn’t a good idea for you to carelessly treat me after I almost died…Don’t you think so? Saiyans can steadily increase their battle power each time they recover from near death…”
Kuririn: “So…so that’s it…! Now that he mentions it, Goku also got stronger every time he had a fierce fight…Dam-dammit! So that’s why Vegeta’s ki has risen so darn much…!”

Then you have this statement, which is specifically about the Saiyan Zenkai. Krillin's additional statement doesn't seem as precise as Vegeta's, though one could say a "fierce fight" could be Krillin's equivalent of what Vegeta was talking about. Goku had some pretty fierce fights during DB with Chun, Tao, Tien, and both Piccolo's. Krillin noted that Goku had become even stronger than he was at the Budokai when he was thrashing General Blue. Seems like that improvement would've come from his battle with Chun.

Now Piccolo's slight increase:

Piccolo was 322 a day before, but got a little boost since then. Do you think he got that from the Raditz battle? Or was he likely scouted at a time where he began training?

 

[withheldforprivacy]

1. Everybody increases his strength after a hard fight/workout, even in real life.
In Saiyans' case, the increase is more noticeable.

2. Krillin confused the first case (noticeable increase after a good fight/workout)
with the zenkai trait.

3. Kid Goku's increases after a good fight...
-21st TB
-Muscle Tower
-22nd TB

Kid Goku's zenkais...
-Post Young Piccolo
-Post Piccolo Jr
(Not sure about Old Piccolo. Some people say it was a zenkai because his heart
had stopped. On the other hand, he didn't seem near death and he could even
walk with no treatment).

 

[Captain Cadaver]

Most character traits got ignored and retconned into Saiyan traits if Goku shared them with other characters from the Freeza Arc and onwards. For instance, his love for battle was changed into a Saiyan trait rather than purely his own personality, despite characters like Piccolo or Ten having similar levels of battle lust due to their pride as martial artists. I think it was a case of Toriyama trying to bring more prominence to the Saiyans at the expense of demoting other characters, something we know would not be just a one time thing.

Finding an in-universe explanation, my guess is that Withheld's first point is correct as obviously irl tougher workout = greater gainz. Most likely, Saiyans get somewhat more Gainz than most other races from similar conditions, something that would become even more apparent in the Cell and Boo Arcs.

 

[Evil Vegeta]

Do you guys think the same applied to Piccolo when he went from 322-329 in a day after the Raditz fight?

If anything, you'd think his power went down after he had to regenerate and use a lot of power destroying the moon.

 

[Captain Cadaver]

Quite an amount of time passed between the Raditz fight and Bulma scanning his battle power, with her having been up all night programming the Scouter and it having not even been evening at Kame House by the time of Goku's death. Piccolo was in an area with a lot of water, so it wouldn't be crazy to assume he hydrated himself back to normal offscreen.

I'd assume Piccolo would benefit from the logic of fighters progressing from a tough challenge in that instance, especially considering his regeneration factor probably gives him the stamina to go harder than most others in training. Could also explains his gainz on Kaio's and in the 3 year training to some extent.

 

[SSJ2]

Might be a dumb q, but was Piccolo factually 100% power during the 322 reading?

 

[Evil Vegeta]

Well, it was his weighted level and I assumed he blasted Raditz with all of his might there. I assume the 329 was his slightly increased weighted level.

 

[SSJ2]

Wasn't he measured before it though? He could have just been slightly suppressed.

 

[Evil Vegeta]

He was also measured at 322 when he and Goku went to fight Raditz, too. In fact, Raditz says the powers were exactly the same as they were earlier.

I don't think they really did too much suppressing there. The weights seemed to do just that.

 

[Victorious]

It's pretty obvious, fighting is essentially a form of training. Goku in the Red Ribbon arc went through no training, yet his power increased from the last time Krillin saw him...since he had fought plenty of foes including the Muscle Tower gauntlet.

We know characters get stronger with training. And the stronger the opponent the stronger the increase is true as well..because that's just reflective of the intensity of the training. Goku get's higher gains from training on 100x gravity than he would if he just trained on 50x gravity the whole time. Vegeta killing Namekian warriors would have probably yielded nothing, but fighting someone on his level would increase his power.