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BOSTON MARATHON 2025

Nicholas Kosiek

Bib: 4158•M

IL

0:00
0:00
/ mi
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Overall
#0 / 28404
Top 12%
Gender (Male)
#0 / 16105
Top 20%
Division (M18-39)
#0 / 5642
Top 44%
Race Day Weather
50°/40°F
broken clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
20:01
Rank: #3426
Start → 5K
20:01 | 6:27/mi
10K· 6.21 mi
40:20
Rank: #3712 (-286)
5K → 10K
20:19 | 6:32/mi
15K· 9.32 mi
1:00:44
Rank: #3813 (-101)
10K → 15K
20:24 | 6:34/mi
20K· 12.43 mi
1:21:16
Rank: #3761 (+52)
15K → 20K
20:32 | 6:37/mi
Half· 13.11 mi
1:25:42
Rank: #3752 (+9)
20K → Half
4:26 | 6:30/mi
25K· 15.53 mi
1:41:54
Rank: #3753 (-1)
Half → 25K
16:12 | 6:41/mi
30K· 18.64 mi
2:03:28
Rank: #3778 (-25)
25K → 30K
21:34 | 6:56/mi
20M
2:13:01
Rank: #3777 (+1)
30K → 20M
9:33 | 7:02/mi
21M
2:20:15
Rank: #3717 (+60)
20M → 21M
7:14 | 7:14/mi
35K· 21.75 mi
2:25:22
Rank: #3729 (-12)
21M → 35K
5:07 | 6:50/mi
23M
2:34:05
Rank: #3677 (+52)
35K → 23M
8:43 | 6:58/mi
24M
2:40:52
Rank: #3629 (+48)
23M → 24M
6:47 | 6:47/mi
40K· 24.85 mi
2:46:44
Rank: #3572 (+57)
24M → 40K
5:52 | 6:52/mi
25.2M
2:49:22
Rank: #3563 (+9)
40K → 25.2M
2:38 | 7:38/mi
Finish· 26.22 mi
2:56:06
Rank: #3516 (+47)
25.2M → Finish
6:44 | 6:36/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:25:42
Pace6:32 /mi
2nd Half
Distance13.11 mi
Time1:30:24
Pace6:54 /mi
📊Positive Split: 5.5% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:22:1920:016:2720:01
6:27
-
10K
6.21 mi10:42:3840:206:2920:19
6:32
+0:05
15K
9.32 mi11:03:021:00:446:3120:24
6:34
+0:02
20K
12.43 mi11:23:341:21:166:3220:32
6:37
+0:03
Half
13.11 mi11:28:001:25:426:324:26
6:30
-0:07
25K
15.53 mi11:44:121:41:546:3416:12
6:41
+0:11
30K
18.64 mi12:05:462:03:286:3721:34
6:56
+0:15
20M
20.00 mi12:15:192:13:016:399:33
7:02
+0:06
21M
21.00 mi12:22:332:20:156:417:14
7:14
+0:12
35K
21.75 mi12:27:402:25:226:415:07
6:50
-0:24
23M
23.00 mi12:36:232:34:056:428:43
6:58
+0:08
24M
24.00 mi12:43:102:40:526:426:47
6:47
-0:11
40K
24.85 mi12:49:022:46:446:425:52
6:52
+0:05
25.2M
25.20 mi12:51:402:49:226:432:38
7:38
+0:46
Finish
26.22 mi12:58:242:56:066:436:44
6:36
-1:02

Checkpoints & Pacing

📈Pace Line

Pace Progression

Track your pace changes throughout the race. Dot colors mark your quickest to easiest segments, relative to your own pace.

Fastest Pace

6:27 /mi

Average Pace

6:43 /mi

Slowest Pace

7:38 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:46:14

94% of race

Time at Steady Pace

7:14

4% of race

Time at Slower Pace

2:38

1% of race

Average Pace: 6:43 /mi

Loading chart...
Faster pace (< avg)
Steady pace (≈ avg)
Slower pace (> avg)

🎨Heatmap

Pace Heatmap

Where you sped up and eased off relative to your own pace across the race. Colors are relative to your own range, not to other runners.

Loading...
0mi6.6mi13.1mi19.7mi26.2mi
Pace:
Faster
Steady
Slower

Click or hover over segments to see details

✨Sparklines

Checkpoint Splits with Pace Trends

Overall Pace Trend

CheckpointDistanceTime of DayTimeAvg PaceSegmentPaceTrendRank
5K
3.11 mi10:22:1920:016:2720:01
6:27
#3426
10K
6.21 mi10:42:3840:206:2920:19
6:32
#3712
15K
9.32 mi11:03:021:00:446:3120:24
6:34
#3813
20K
12.43 mi11:23:341:21:166:3220:32
6:37
#3761
Half
13.11 mi11:28:001:25:426:324:26
6:30
#3752
25K
15.53 mi11:44:121:41:546:3416:12
6:41
#3753
30K
18.64 mi12:05:462:03:286:3721:34
6:56
#3778
20M
20.00 mi12:15:192:13:016:399:33
7:02
#3777
21M
21.00 mi12:22:332:20:156:417:14
7:14
#3717
35K
21.75 mi12:27:402:25:226:415:07
6:50
#3729
23M
23.00 mi12:36:232:34:056:428:43
6:58
#3677
24M
24.00 mi12:43:102:40:526:426:47
6:47
#3629
40K
24.85 mi12:49:022:46:446:425:52
6:52
#3572
25.2M
25.20 mi12:51:402:49:226:432:38
7:38
#3563
Finish
26.22 mi12:58:242:56:066:436:44
6:36
#3516
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi3426325532553993(Top 14%)3763(Top 23%)3763(Top 67%)
10K6.21 mi3.10 mi3712-2863518-2633518-2634007(Top 14%)3772(Top 23%)3772(Top 67%)
15K9.32 mi3.11 mi3813-1013599-813599-813993(Top 14%)3763(Top 23%)3763(Top 67%)
20K12.43 mi3.11 mi3761+523550+493550+493760(Top 13%)3550(Top 22%)3550(Top 63%)
Half13.11 mi0.68 mi3752+93542+83542+83698(Top 13%)3498(Top 22%)3498(Top 62%)
25K15.53 mi2.42 mi3753-1354235424000(Top 14%)3732(Top 23%)3732(Top 66%)
30K18.64 mi3.11 mi3778-253561-193561-194347(Top 15%)3982(Top 25%)3982(Top 71%)
20M20.00 mi1.36 mi3777+13556+53556+54285(Top 15%)3908(Top 24%)3908(Top 69%)
21M21.00 mi1.00 mi3717+603495+613495+613297(Top 12%)3035(Top 19%)3035(Top 54%)
35K21.75 mi0.75 mi3729-123505-103505-104364(Top 15%)3893(Top 24%)3893(Top 69%)
23M23.00 mi1.25 mi3677+523449+563449+563542(Top 12%)3212(Top 20%)3212(Top 57%)
24M24.00 mi1.00 mi3629+483399+503399+503418(Top 12%)3073(Top 19%)3073(Top 54%)
40K24.85 mi0.85 mi3572+573338+613338+613175(Top 11%)2848(Top 18%)2848(Top 50%)
25.2M25.20 mi0.35 mi3563+93328+103328+104054(Top 14%)3470(Top 22%)3470(Top 62%)
Finish26.22 mi1.02 mi3516+473282+463282+463380(Top 12%)2964(Top 18%)2964(Top 53%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 14%
×21stories
+97ft-345ft

Overall

3993

Males

3763

M18-39

3763

5K→10K

3.1 - 6.2 mi

Top 14%
×5stories
+79ft-138ft

Overall

4007

Males

3772

M18-39

3772

10K→15K

6.2 - 9.3 mi

Top 14%
×3stories
+67ft-78ft

Overall

3993

Males

3763

M18-39

3763

15K→20K

9.3 - 12.4 mi

Top 13%
×5stories
+106ft-86ft

Overall

3760

Males

3550

M18-39

3550

20K→Half

12.4 - 13.1 mi

Top 13%
×2stories
+19ft-37ft

Overall

3698

Males

3498

M18-39

3498

Half→25K

13.1 - 15.5 mi

Top 14%
×4stories
+66ft-88ft

Overall

4000

Males

3732

M18-39

3732

25K→30K

15.5 - 18.6 mi

Top 15%
×9stories
+181ft-148ft

Overall

4347

Males

3982

M18-39

3982

30K→20M

18.6 - 20.0 mi

Top 15%
×5stories
+64ft-50ft

Overall

4285

Males

3908

M18-39

3908

20M→21M

20.0 - 21.0 mi

Top 12%
×8stories
+106ft-24ft

Overall

3297

Males

3035

M18-39

3035

21M→35K

21.0 - 21.8 mi

Top 15%
×7stories
+17ft-86ft

Overall

4364

Males

3893

M18-39

3893

35K→23M

21.8 - 23.0 mi

Top 12%
×5stories
+23ft-63ft

Overall

3542

Males

3212

M18-39

3212

23M→24M

23.0 - 24.0 mi

Top 12%
×6stories
+12ft-82ft

Overall

3418

Males

3073

M18-39

3073

24M→40K

24.0 - 24.9 mi

Top 11%
×1story
+6ft-20ft

Overall

3175

Males

2848

M18-39

2848

40K→25.2M

24.9 - 25.2 mi

Top 14%
×1story
+13ft-16ft

Overall

4054

Males

3470

M18-39

3470

25.2M→Finish

25.2 - 26.2 mi

Top 12%
×2stories
+22ft-21ft

Overall

3380

Males

2964

M18-39

2964

Passing Analysis

Category:
Athletes Passed
913
Passed By
1003
Net Change
-90
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#3426
5K → 10K36322-286#3426#3712
10K → 15K64165-101#3712#3813
15K → 20K11462+52#3813#3761
20K → Half2314+9#3761#3752
Half → 25K7980-1#3752#3753
25K → 30K95120-25#3753#3778
30K → 20M6463+1#3778#3777
20M → 21M8121+60#3777#3717
21M → 35K2941-12#3717#3729
35K → 23M8331+52#3729#3677
23M → 24M7426+48#3677#3629
24M → 40K7619+57#3629#3572
40K → 25.2M2819+9#3572#3563
25.2M → Finish6720+47#3563#3516
TOTALS9131003-90
📊

Passing Visuals

Category:
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🔥Passing Intensity

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🔄Passing Circle

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🌊Position Flow

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🏃Race Lanes

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Public Race Data

Boston Athletic Association

Boston Athletic Association

Mika Timing

Mika Timing