| POS | ATHLETE | COUNTRY | MARK | Reaction Time |
|---|---|---|---|---|
| 1 | Russia Junior |
RUS
|
40.06 Q PB | 0.133 |
| 2 | Germany Junior |
GER
|
40.07 Q | 0.167 |
| 3 | Australia Junior |
AUS
|
40.11 SB | 0.141 |
| 4 | Japan Junior |
JPN
|
40.17 SB | 0.174 |
| 5 | Oman Junior |
OMA
|
40.53 SB | 0.197 |
| 6 | Cayman Islands Junior |
CAY
|
40.92 NJ | 0.147 |
| 7 | Italy Junior |
ITA
|
41.59 SB | 0.176 |
| POS | ATHLETE | COUNTRY | MARK | Reaction Time |
|---|---|---|---|---|
| 1 | United States Junior |
USA
|
39.50 Q WJL | 0.163 |
| 2 | Canada Junior |
CAN
|
39.64 Q NJ | 0.154 |
| 3 | Poland Junior |
POL
|
39.84 q SB | 0.166 |
| 4 | Thailand Junior |
THA
|
39.92 SB | 0.175 |
| 5 | Spain Junior |
ESP
|
40.22 PB | 0.148 |
| 6 | Sweden Junior |
SWE
|
40.28 SB | 0.158 |
| 7 | Senegal Junior |
SEN
|
43.21 SB | 0.155 |
| PR of China Junior |
CHN
|
DQ | 0.188 |
| POS | ATHLETE | COUNTRY | MARK | Reaction Time |
|---|---|---|---|---|
| 1 | Jamaica Junior |
JAM
|
39.18 Q WJL | 0.178 |
| 2 | Great Britain & N.I. Junior |
GBR
|
39.30 Q SB | 0.162 |
| 3 | Nigeria Junior |
NGR
|
39.68 q SB | 0.166 |
| 4 | France Junior |
FRA
|
40.16 SB | 0.170 |
| 5 | Chinese Taipei Junior |
TPE
|
40.33 NJ | 0.136 |
| 6 | South Africa Junior |
RSA
|
40.36 SB | 0.188 |
| 7 | Singapore U20 |
SGP
|
41.74 NJ | 0.171 |