Swimmer profile
Mac Koster
Male15-16YMCA of the Jersey ShoreNJ · EASTERN
SeasonUSA Swimming season runs Sept – Aug
Event
2021–22
2022–23
2023–24
2024–25
2025–26
50 Free LCM
29.47
28.44
▲ 1.03
27.56
▲ 0.88
27.24
▲ 0.32
26.94
▲ 0.30
100 Free LCM
1:04.66
1:03.13
▲ 1.53
1:03.93
▼ 0.80
1:00.76
▲ 3.17
59.73
▲ 1.03
200 Free LCM
2:21.22
—
2:27.36
▼ 6.14
—
—
400 Free LCM
5:10.94
—
—
—
—
50 Back LCM
35.73
33.78
▲ 1.95
31.33
▲ 2.45
31.56
▼ 0.23
30.67
▲ 0.89
100 Back LCM
1:14.09
1:10.75
▲ 3.34
1:05.59
▲ 5.16
1:06.97
▼ 1.38
1:07.29
▼ 0.32
200 Back LCM
2:36.99
2:38.06
▼ 1.07
2:26.12
▲ 11.94
2:28.91
▼ 2.79
2:26.27
▲ 2.64
50 Breast LCM
44.04
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—
—
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50 Fly LCM
34.13
32.36
▲ 1.77
29.70
▲ 2.66
29.18
▲ 0.52
30.26
▼ 1.08
100 Fly LCM
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—
1:10.74
1:07.12
▲ 3.62
1:06.67
▲ 0.45
200 IM LCM
2:44.14
2:51.75
▼ 7.61
2:40.31
▲ 11.44
2:35.21
▲ 5.10
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Improvement<0.5s0.5–2s2–5s5s+Slower
📊 All Attempts by Event
Chronological history of every recorded swim. Click an event to expand its attempt list.