Ronald Dalmacio of Rose Bowl Breaks 59 in 100 Back, Lowers Own 10&U NAG Record at Far Westerns

10-year old Ronald Dalmacio of Rose Bowl Aquatics Swim Team lowered his own National Age Group Record in the boys’ 10-and-under 100 yard back on Saturday at 2015 Far Westerns Championships, going 58.62.

Dalmacio first broke Destin Lasco’s 2012 mark of 59.81 in February at the Southern California Swimming Club Championships. He went just under with 59.76 in prelims, then took another .71 off in finals. This weekend marks the third time this year he has eclipsed Lasco’s NAG record, and now he has re-written the books by 1.2 seconds.

Comparative splits:
Lasco, 2012 29.13/30.68 = 59.81
Dalmacio, February 2015 (prelims) 29.56/30.20 = 59.76
Dalmacio, February 2015 (finals) 29.29/29.76 = 59.05
Dalmacio, April 2015 (finals) 28.67/29.95 = 58.62


Dalmacio seems to have been working on his up-front speed in the two months since he first broke the record; he was out nearly a second faster than his first record, and home .25 better.

You can follow the results of 2015 Far Westerns here.

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5 years ago

Yikes! I thought Lasco’s records would last a LONG time! Congratulations, Mr Dalmacio!

Swim Mom
5 years ago

Josh Zuchowski went 59.61 in the 10 under 100 back this weekend at NASA which is also lower then Destin Lasco’s previous mark.

Josh also went 2:12.67 in the 200 IM. He just missed Chas Morton’s 2:12.29 from 1982. This puts him second all time and over 2 seconds ahead of 3rd.

Replays available on

Reply to  Swim Mom
5 years ago

It sounds like there will be an article about Josh here soon!

Lane Four
5 years ago

Video? A TEN-YEAR-OLD BOY swims the 100 back in 58 seconds?????????? Backstroke!!! In 58 seconds!!!!! Speechless. congratulations!

About Anne Lepesant

Anne Lepesant

Anne Lepesant is the mother of four daughters, all of whom swim/swam in college. With an undergraduate degree from Princeton (where she was an all-Ivy tennis player) and an MBA from INSEAD, she worked for many years in the financial industry, both in France and the U.S. Anne is currently …

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