US thrower Adrian Piperi secured the gold medal in the boys&rsquo; shot and finished sixth in the boys&rsquo; discus at the IAAF World Youth Championships Cali 2015. Here the 16-year-old offers his take on our personal bests questions.<h3>My greatest rival</h3>I have a few. In the discus it would probably be Gabe (Gabriel Oladipo, who finished ninth in the discus at the World Youth Championships) and Isaiah (Rogers, who finished 10th in the boys&rsquo; shot in Cali). Another would be Jordan Geist, a rival of mine in both the shot and discus. Gabe and I are good competitors and good friends.<h3>My best achievement in athletics </h3>Winning gold at the World Youth Championships. Holding the flag aloft was an amazing experience that you don&rsquo;t get to feel too often. I have never felt that happy. I felt huge pride representing the United States. It was one of the most amazing feelings.<h3>My greatest disappointment</h3>I remember competing awfully one year at the Junior Olympics. I had a very bad day. I finished third and threw 30ft under my PR. I was very upset. I know it sounds bad to say because I did finish third in the competition, but if you threw 30ft under your PR you would understand. Up until that point I had won most competitions and it came as a shock but it finally taught me to learn how to lose and I rebounded back the next week. <h3>My greatest indulgence</h3>Netflix. When I&rsquo;m bored, I watch Netflix. I&rsquo;ve been watching Hawaii Five-0, Archer and Psych. <h3>The best competition venue</h3>By far the biggest stadium I have ever competed in is the Pascual Guerrero Stadium in Cali, Colombia. It was huge and I really enjoyed competing there. It was probably three times bigger than any stadium I have competed at in the US, which is crazy to think.<h3>The best athlete I have ever seen</h3>Probably Adam Nelson (the 2004 Olympic shot put champion). I have personally got to know him. He&rsquo;s been a big influence on me and helped me out a lot. Adam also definitely helped create more interest in the shot. It is now much more in the public eye. It is crazy to think how much it has grown in the past 10 years.<h3>The best piece of coaching advice</h3>It is to stay calm. This is especially true in the discus. I find in the shot I can get really fired up when throwing but because the discus is more technical I have to really calm down. Discus is a bit like golf in that if you try too hard, you screw up. <h3>My best friend in track and field</h3>I would say all of my team-mates at school. We are like a family. Steve Landells for the IAAF

US thrower Adrian Piperi secured the gold medal in the boys’ shot and finished sixth in the boys’ discus at the IAAF World Youth Championships Cali 2015. Here the 16-year-old offers his take on our personal bests questions.

Personal bests – Adrian Piperi

An impressive championship record of 10.28 in the boys&rsquo; 100m by Japan&rsquo;s Abdul Hakim Sani Brown capped an entertaining opening day of the IAAF World Youth Championships, Cali 2015 on Wednesday (15).Sani Brown&rsquo;s dominant victory in the Colombian city came in one of the four finals in a breezy Pascual Guerrero Stadium, but was certainly the most impressive.The 16-year-old arrived in Cali with a 10.30 personal best from May, one he equalled in this morning&rsquo;s opening round and again in the semi-finals. In the final, it was clearly a battle of Sani Brown against the clock from 40 metres onwards when he began to extend his lead with every stride. Improbably, he stopped the clock in 10.29, which was later adjusted by another notch in his favour to land him on the doorstep of the event&rsquo;s all-time top-ten.Derrick Silva of Brazil was a distant second in 10.49 with Great Britain&rsquo;s Rechmial Miller crossing the line in 10.59 for third.Adrian Piperi took command of the boys&rsquo; shot put in the second round with a national youth record of 22.00m to collect the USA&rsquo;s second gold in the event. It was an improvement of nearly a metre for the 16-year-old, one he managed to match with his throw in the final round and which catapulted him to the top of the world season&rsquo;s list and ninth on the world youth all-time list.Poland&rsquo;s Szymon Mazur was second with 21.77m while Sweden&rsquo;s Wictor Petersson took the bronze with 21.56m, personal bests for both athletes.Shuru Bulo of Ethiopia took a convincing victory in the girls&rsquo; 3000m, an event all but dominated by Kenya at these championships&rsquo; previous eight editions. Bulo, relatively unheralded prior to her arrival in Cali, took the lead with 200 metres remaining en route to her 9:01.12 performance, a world-youth-leading time. Kenya&rsquo;s Emily Chebet Kipchumba, who ran at the front for most of the race, finished second in 9:02.92, just ahead of teammate Sheila Chelangat.<h3>Emilianov's discus delight&nbsp; </h3>The fourth title of the day went to Moldova&rsquo;s Alexandra Emilianov who produced a minor upset in the girls&rsquo; discus.&nbsp; Emilianov threw a 52.78m personal best in the second round to take the lead for good from Montenegro&rsquo;s Kristina Rakocevic whose best on the day was a 51.14m effort, also from round two. Samantha Peace of Australia took the bronze, her 50.59m also a career best and the first medal in the event for Australia since Dani Samuels&rsquo; victory in 2005.In the decathlon at the halfway point, France&rsquo;s Ludovic Besson of France will carry a 29-point lead into the second day of these championships&rsquo; inaugural decathlon competition. The 17-year-old produced personal bests in four events &ndash; 10.97 in the 100m, 7.05m in the long jumps, 1.87m in the high jump and 49.93 in the 400m &ndash; to tally 4106 points, marginally ahead of the USA&rsquo;s George Patrick, who collected 4077. Patrick also notched four personal bests of his own: 7.26m in the long jump, 15.54m in the shot put, 1.96m in the high jump and 50.54 in the 400m.Propelled by 10.93 and 7.53m performances in the 100m and long jump, Hans-Christian Hausenberg sits in third with 4075 points. Germany's Niklas Kaul will also move up the standings on day two as his strongest event, the javelin, is yet to come.Ryusei Fujii of Japan led all qualifiers in the 400m hurdles with a 50.87 run, a personal best by more than half a second. Nearly as fast was the USA&rsquo;s Norman Grimes, who won heat five in 50.95.In the women&rsquo;s contest, USA's world youth leader Sydney McLaughlin solidified her favourite&rsquo;s role with a comfortable 56.81 victory in the opening heat, more than a second faster than anyone else.<h3>Amano looks a little like Aman</h3>Omer Amano made his ambitions to become the first 800m champion from Ethiopia quite clear with a confident 1:50.31 victory in the fifth heat to lead all qualifiers into Thursday evening&rsquo;s semi-finals. Other heat winners included Kenyans Willy Kiplimo Tarbei (1:50.92) and Kipyegon Bett (1:51.38) and Great Britain&rsquo;s Ben Greenwood (1:51.58). Meanwhile, Kenya looks to be on target for a second successive 1-2 finish in the girls&rsquo; 2000m steeplechase, courtesy of Sandrafelis Chebet Tuei and Celliphinie Chepteek Chespol. The pair dominated the evening&rsquo;s two opening round heats winning in 6:26.70 and 6:31.97 respectively. In the boys' triple jump qualifiers, world youth leader and pre-event favourite Cristian Atanay Napoles of Cuba led the round with a 15.98m effort, marginally ahead of China&rsquo;s Du Mingze who improved his career bet to 15.82m. In the girls&rsquo; javelin, Czech Republic&rsquo;s Nikol Tabackova topped the round with a 55.29m effort, with Germany&rsquo;s Lotte Reimann also throwing beyond 54 metres with 54.35m to her name.Day two action kicks off at 09:30 local time with the decathlon 110m hurdles. The evening will witness new champions crowned in the girls&rsquo; 100m, 100m hurdles, shot put and javelin, and in the decathlon and long jump on the boys&rsquo; programme.Bob Ramsak for the IAAF

An impressive championship record of 10.28 in the boys’ 100m by Japan’s Abdul Hakim Sani Brown capped an entertaining opening day of the IAAF World Youth Championships, Cali 2015 on Wednesday (15).

Sani Brown provides the highlights of the opening day in Cali

A near one-metre improvement enabled US shot putter Adrian
Piperi to secure the first gold medal of the IAAF World Youth Championships, Cali 2015 inside a breezy Pascual Guerrero
Stadium on Wednesday evening (15). In a competition which witnessed a blizzard of personal best
marks among the leading contenders, it was the Texan who prevailed courtesy of
a mighty second round heave of 22.00m, 94cm further than his previous best &ndash; a
distance he was to coincidentally match with his final throw.&nbsp; Behind, both Szymon Mazur of Poland (21.77m) and Wictor
Petersson of Sweden (21.56m) also shattered their best marks to claim silver
and bronze, respectively.&nbsp; In fact, in a results sheet that will lift the heart, the
top seven were credited with lifetime bests. Petersson led after round one with 20.87m followed by Mazur
20.44m, with Piperi making an early claim on bronze with 20.02m before the
competition exploded into life in round two. Firstly, South African Burger Lambrechts, hurled the 5kg
ball out to 20.87m to precisely match the distance first achieved by the Petersson.
In a bizarre quirk, the fast-spinning Swede then registered 20.87m for the
second time to briefly lead.However, Piperi made the competition much more clear cut, punching
the air in delight after recording a monster 2015 world youth leading distance
of 22.00m to take a firm control of the competition. The main mover in round three was the giant Pole, Mazur who
advanced from fifth to a solid silver position, adding 49cm to his personal
best with a 21.66m effort.&nbsp; There was no overall movement in the top three in round
four, although both Mazur with 21.77m and Petersson 21.56m solidified their
silver and bronze medal positions.Round fives and six provided no change to the overall picture,
although Piperi, with the gold medal in his pocket, further demonstrated his
superiority today by once again hurling the shot out to 22.00m with the final
act of the competition. He held his hand aloft in triumph following the throw. a
worthy winner. Steve Landells for
the IAAF&nbsp;

A near one-metre improvement enabled US shot putter Adrian Piperi to secure the first gold medal of the IAAF World Youth Championships, Cali 2015 inside a breezy Pascual Guerrero Stadium on Wednesday evening (15). 

Personal bests – Adrian Piperi

Sani Brown provides the highlights of the opening day in Cali

Boys' shot put – IAAF World Youth Championships, Cali 2015