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BOSTON MARATHON 2023

David Szostak

Bib: 7049•M

NJ

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Top 13%
Gender (Male)
#0 / 15176
Top 22%
Masters (Masters Men)
#0 / 9891
Top 9%
Division (M45-49)
#0 / 2252
Top 11%
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
21:06
Rank: #4587
Start → 5K
21:06 | 6:47/mi
10K· 6.21 mi
41:58
Rank: #4520 (+67)
5K → 10K
20:52 | 6:43/mi
15K· 9.32 mi
1:02:46
Rank: #4358 (+162)
10K → 15K
20:48 | 6:42/mi
20K· 12.43 mi
1:23:39
Rank: #4174 (+184)
15K → 20K
20:53 | 6:43/mi
Half· 13.11 mi
1:28:11
Rank: #4149 (+25)
20K → Half
4:32 | 6:39/mi
25K· 15.53 mi
1:44:27
Rank: #4000 (+149)
Half → 25K
16:16 | 6:43/mi
30K· 18.64 mi
2:05:29
Rank: #3698 (+302)
25K → 30K
21:02 | 6:46/mi
20M
2:14:41
Rank: #3568 (+130)
30K → 20M
9:12 | 6:46/mi
21M
2:22:05
Rank: #3579 (-11)
20M → 21M
7:24 | 7:24/mi
35K· 21.75 mi
2:27:08
Rank: #3582 (-3)
21M → 35K
5:03 | 6:45/mi
23M
2:35:43
Rank: #3494 (+88)
35K → 23M
8:35 | 6:51/mi
24M
2:42:28
Rank: #3475 (+19)
23M → 24M
6:45 | 6:45/mi
40K· 24.85 mi
2:48:18
Rank: #3432 (+43)
24M → 40K
5:50 | 6:49/mi
25.2M
2:50:55
Rank: #3442 (-10)
40K → 25.2M
2:37 | 7:35/mi
Finish· 26.22 mi
2:57:57
Rank: #3475 (-33)
25.2M → Finish
7:02 | 6:54/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:28:11
Pace6:44 /mi
2nd Half
Distance13.11 mi
Time1:29:46
Pace6:51 /mi
📊Positive Split: 1.8% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:25:0621:066:4721:06
6:47
-
10K
6.21 mi10:45:5841:586:4520:52
6:43
-0:04
15K
9.32 mi11:06:461:02:466:4420:48
6:42
-0:01
20K
12.43 mi11:27:391:23:396:4420:53
6:43
+0:01
Half
13.11 mi11:32:111:28:116:444:32
6:39
-0:04
25K
15.53 mi11:48:271:44:276:4316:16
6:43
+0:04
30K
18.64 mi12:09:292:05:296:4421:02
6:46
+0:03
20M
20.00 mi12:18:412:14:416:449:12
6:46
0:00
21M
21.00 mi12:26:052:22:056:467:24
7:24
+0:38
35K
21.75 mi12:31:082:27:086:465:03
6:45
-0:39
23M
23.00 mi12:39:432:35:436:468:35
6:51
+0:06
24M
24.00 mi12:46:282:42:286:466:45
6:45
-0:06
40K
24.85 mi12:52:182:48:186:465:50
6:49
+0:04
25.2M
25.20 mi12:54:552:50:556:472:37
7:35
+0:46
Finish
26.22 mi13:01:572:57:576:487:02
6:54
-0:41

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

6:39 /mi

Average Pace

6:48 /mi

Slowest Pace

7:35 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:47:56

94% of race

Time at Steady Pace

10:01

6% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 6:47 /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 mi10:25:0621:066:4721:06
6:47
#4587
10K
6.21 mi10:45:5841:586:4520:52
6:43
#4520
15K
9.32 mi11:06:461:02:466:4420:48
6:42
#4358
20K
12.43 mi11:27:391:23:396:4420:53
6:43
#4174
Half
13.11 mi11:32:111:28:116:444:32
6:39
#4149
25K
15.53 mi11:48:271:44:276:4316:16
6:43
#4000
30K
18.64 mi12:09:292:05:296:4421:02
6:46
#3698
20M
20.00 mi12:18:412:14:416:449:12
6:46
#3568
21M
21.00 mi12:26:052:22:056:467:24
7:24
#3579
35K
21.75 mi12:31:082:27:086:465:03
6:45
#3582
23M
23.00 mi12:39:432:35:436:468:35
6:51
#3494
24M
24.00 mi12:46:282:42:286:466:45
6:45
#3475
40K
24.85 mi12:52:182:48:186:465:50
6:49
#3432
25.2M
25.20 mi12:54:552:50:556:472:37
7:35
#3442
Finish
26.22 mi13:01:572:57:576:487:02
6:54
#3475
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM45-49Seg. OverallSeg. MalesSeg. M45-49
5K3.11 mi3.11 mi4587427542754068(Top 15%)3817(Top 25%)3817(Top 169%)
10K6.21 mi3.10 mi4520+674223+524223+524488(Top 17%)4193(Top 28%)4193(Top 186%)
15K9.32 mi3.11 mi4358+1624078+1454078+1454068(Top 15%)3817(Top 25%)3817(Top 169%)
20K12.43 mi3.11 mi4174+1843916+1623916+1623737(Top 14%)3531(Top 23%)3531(Top 157%)
Half13.11 mi0.68 mi4149+253894+223894+223775(Top 14%)3559(Top 23%)3559(Top 158%)
25K15.53 mi2.42 mi4000+1493763+1313763+1313422(Top 13%)3243(Top 21%)3243(Top 144%)
30K18.64 mi3.11 mi3698+3023494+2693494+2692815(Top 11%)2671(Top 18%)2671(Top 119%)
20M20.00 mi1.36 mi3568+1303375+1193375+1192661(Top 10%)2518(Top 17%)2518(Top 112%)
21M21.00 mi1.00 mi3579-113387-123387-124106(Top 15%)3775(Top 25%)3775(Top 168%)
35K21.75 mi0.75 mi3582-33388-13388-13846(Top 14%)3540(Top 23%)3540(Top 157%)
23M23.00 mi1.25 mi3494+883302+863302+862972(Top 11%)2773(Top 18%)2773(Top 123%)
24M24.00 mi1.00 mi3475+193284+183284+183371(Top 13%)3108(Top 20%)3108(Top 138%)
40K24.85 mi0.85 mi3432+433242+423242+422946(Top 11%)2713(Top 18%)2713(Top 120%)
25.2M25.20 mi0.35 mi3442-103252-103252-104259(Top 16%)3729(Top 25%)3729(Top 166%)
Finish26.22 mi1.02 mi3475-333275-233275-234607(Top 17%)3996(Top 26%)3996(Top 177%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 15%
×21stories
+97ft-345ft

Overall

4068

Males

3817

M45-49

3817

5K→10K

3.1 - 6.2 mi

Top 17%
×5stories
+79ft-138ft

Overall

4488

Males

4193

M45-49

4193

10K→15K

6.2 - 9.3 mi

Top 15%
×3stories
+67ft-78ft

Overall

4068

Males

3817

M45-49

3817

15K→20K

9.3 - 12.4 mi

Top 14%
×5stories
+106ft-86ft

Overall

3737

Males

3531

M45-49

3531

20K→Half

12.4 - 13.1 mi

Top 14%
×2stories
+19ft-37ft

Overall

3775

Males

3559

M45-49

3559

Half→25K

13.1 - 15.5 mi

Top 13%
×4stories
+66ft-88ft

Overall

3422

Males

3243

M45-49

3243

25K→30K

15.5 - 18.6 mi

Top 11%
×9stories
+181ft-148ft

Overall

2815

Males

2671

M45-49

2671

30K→20M

18.6 - 20.0 mi

Top 10%
×5stories
+64ft-50ft

Overall

2661

Males

2518

M45-49

2518

20M→21M

20.0 - 21.0 mi

Top 15%
×8stories
+106ft-24ft

Overall

4106

Males

3775

M45-49

3775

21M→35K

21.0 - 21.8 mi

Top 14%
×7stories
+17ft-86ft

Overall

3846

Males

3540

M45-49

3540

35K→23M

21.8 - 23.0 mi

Top 11%
×5stories
+23ft-63ft

Overall

2972

Males

2773

M45-49

2773

23M→24M

23.0 - 24.0 mi

Top 13%
×6stories
+12ft-82ft

Overall

3371

Males

3108

M45-49

3108

24M→40K

24.0 - 24.9 mi

Top 11%
×1story
+6ft-20ft

Overall

2946

Males

2713

M45-49

2713

40K→25.2M

24.9 - 25.2 mi

Top 16%
×1story
+13ft-16ft

Overall

4259

Males

3729

M45-49

3729

25.2M→Finish

25.2 - 26.2 mi

Top 17%
×2stories
+22ft-21ft

Overall

4607

Males

3996

M45-49

3996

Passing Analysis

Category:
Athletes Passed
1663
Passed By
551
Net Change
+1112
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#4587
5K → 10K243176+67#4587#4520
10K → 15K22260+162#4520#4358
15K → 20K20319+184#4358#4174
20K → Half338+25#4174#4149
Half → 25K16415+149#4149#4000
25K → 30K31311+302#4000#3698
30K → 20M1366+130#3698#3568
20M → 21M4253-11#3568#3579
21M → 35K3639-3#3579#3582
35K → 23M10820+88#3582#3494
23M → 24M4829+19#3494#3475
24M → 40K6623+43#3475#3432
40K → 25.2M1121-10#3432#3442
25.2M → Finish3871-33#3442#3475
TOTALS1663551+1112
📊

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