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BOSTON MARATHON 2023

David Nerrow

Bib: 15887•M

MA

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Gender (Male)
#0 / 15176
Masters (Masters Men)
#0 / 9891
Division (M55-59)
#0 / 1422
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Course Elevation
7–469 ft
≈
×2stacked redwood trees
•▲ 890 ft climb · ▼ 1342 ft descent
Ribbon color based on
FasterSteadySlower· vs. your average pace
Start
0:00
Race begins
5K· 3.11 mi
7:25/mi
23:04
↑ 97↓ 3451.5%
10K· 6.21 mi
7:29/mi
46:18
↑ 79↓ 1380.4%
15K· 9.32 mi
7:26/mi
1:09:23
↑ 67↓ 78
20K· 12.43 mi
7:32/mi
1:32:47
↑ 106↓ 860.1%
Half· 13.11 mi
7:29/mi
1:37:53
↑ 19↓ 370.5%
25K· 15.53 mi
7:46/mi
1:56:44
↑ 66↓ 880.2%
30K· 18.64 mi
9:01/mi
2:24:44
↑ 181↓ 1480.2%
20M
9:56/mi
2:38:14
↑ 64↓ 500.2%
21M
10:32/mi
2:48:46
↑ 106↓ 241.6%
35K· 21.75 mi
10:03/mi
2:56:17
↑ 17↓ 861.7%
23M
11:58/mi
3:11:16
↑ 23↓ 630.6%
24M
12:02/mi
3:23:18
↓ 821.3%
40K· 24.85 mi
13:16/mi
3:34:39
↓ 200.3%
25.2M
14:42/mi
3:39:43
↑ 13↓ 160.2%
Finish· 26.22 mi
12:31/mi
3:52:28
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:37:53
Pace7:28 /mi
2nd Half
Distance13.11 mi
Time2:14:35
Pace10:16 /mi
📊Positive Split: 37.5% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:53:2323:047:2523:04
7:25
-
10K
6.21 mi11:16:3746:187:2723:14
7:29
+0:04
15K
9.32 mi11:39:421:09:237:2723:05
7:26
-0:03
20K
12.43 mi12:03:061:32:477:2823:24
7:32
+0:06
Half
13.11 mi12:08:121:37:537:285:06
7:29
-0:03
25K
15.53 mi12:27:031:56:447:3118:51
7:46
+0:17
30K
18.64 mi12:55:032:24:447:4628:00
9:01
+1:15
20M
20.00 mi13:08:332:38:147:5513:30
9:56
+0:55
21M
21.00 mi13:19:052:48:468:0210:32
10:32
+0:36
35K
21.75 mi13:26:362:56:178:067:31
10:03
-0:29
23M
23.00 mi13:41:353:11:168:1914:59
11:58
+1:55
24M
24.00 mi13:53:373:23:188:2812:02
12:02
+0:04
40K
24.85 mi14:04:583:34:398:3811:21
13:16
+1:14
25.2M
25.20 mi14:10:023:39:438:435:04
14:42
+1:26
Finish
26.22 mi14:22:473:52:288:5212:45
12:31
-2:11

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

7:25 /mi

Average Pace

8:52 /mi

Slowest Pace

14:42 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:56:44

50% of race

Time at Steady Pace

59:33

26% of race

Time at Slower Pace

56:11

24% of race

Average Pace: 8:52 /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 mi10:53:2323:047:2523:04
7:25
#9037
10K
6.21 mi11:16:3746:187:2723:14
7:29
#9584
15K
9.32 mi11:39:421:09:237:2723:05
7:26
#9568
20K
12.43 mi12:03:061:32:477:2823:24
7:32
#9540
Half
13.11 mi12:08:121:37:537:285:06
7:29
#9569
25K
15.53 mi12:27:031:56:447:3118:51
7:46
#9775
30K
18.64 mi12:55:032:24:447:4628:00
9:01
#11286
20M
20.00 mi13:08:332:38:147:5513:30
9:56
#12310
21M
21.00 mi13:19:052:48:468:0210:32
10:32
#12953
35K
21.75 mi13:26:362:56:178:067:31
10:03
#13457
23M
23.00 mi13:41:353:11:168:1914:59
11:58
#14779
24M
24.00 mi13:53:373:23:188:2812:02
12:02
#15675
40K
24.85 mi14:04:583:34:398:3811:21
13:16
#16623
25.2M
25.20 mi14:10:023:39:438:435:04
14:42
#17014
Finish
26.22 mi14:22:473:52:288:5212:45
12:31
#17873
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM55-59Seg. OverallSeg. MalesSeg. M55-59
5K3.11 mi3.11 mi9037762476249602(Top 36%)7929(Top 52%)7929(Top 558%)
10K6.21 mi3.10 mi9584-5477925-3017925-30110278(Top 39%)8322(Top 55%)8322(Top 585%)
15K9.32 mi3.11 mi9568+167913+127913+129602(Top 36%)7929(Top 52%)7929(Top 558%)
20K12.43 mi3.11 mi9540+287882+317882+319564(Top 36%)7841(Top 52%)7841(Top 551%)
Half13.11 mi0.68 mi9569-297903-217903-2110038(Top 38%)8148(Top 54%)8148(Top 573%)
25K15.53 mi2.42 mi9775-2068010-1078010-10710895(Top 41%)8455(Top 56%)8455(Top 595%)
30K18.64 mi3.11 mi11286-15118691-6818691-68117236(Top 65%)11011(Top 73%)11011(Top 774%)
20M20.00 mi1.36 mi12310-10249130-4399130-43920269(Top 76%)12236(Top 81%)12236(Top 860%)
21M21.00 mi1.00 mi12953-6439378-2489378-24819681(Top 74%)11902(Top 78%)11902(Top 837%)
35K21.75 mi0.75 mi13457-5049580-2029580-20221381(Top 80%)12650(Top 83%)12650(Top 890%)
23M23.00 mi1.25 mi14779-132210057-47710057-47723950(Top 90%)13830(Top 91%)13830(Top 973%)
24M24.00 mi1.00 mi15675-89610365-30810365-30824567(Top 92%)14073(Top 93%)14073(Top 990%)
40K24.85 mi0.85 mi16623-94810764-39910764-39925164(Top 95%)14377(Top 95%)14377(Top 1011%)
25.2M25.20 mi0.35 mi17014-39110920-15610920-15625501(Top 96%)14543(Top 96%)14543(Top 1023%)
Finish26.22 mi1.02 mi17873-85911280-36011280-36025693(Top 97%)14643(Top 96%)14643(Top 1030%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 36%
×21story building
+97ft-345ft

Overall

9602

Males

7929

M55-59

7929

5K→10K

3.1 - 6.2 mi

Top 39%
×5story building
+79ft-138ft

Overall

10278

Males

8322

M55-59

8322

10K→15K

6.2 - 9.3 mi

Top 36%
×3story building
+67ft-78ft

Overall

9602

Males

7929

M55-59

7929

15K→20K

9.3 - 12.4 mi

Top 36%
×5story building
+106ft-86ft

Overall

9564

Males

7841

M55-59

7841

20K→Half

12.4 - 13.1 mi

Top 38%
×2story building
+19ft-37ft

Overall

10038

Males

8148

M55-59

8148

Half→25K

13.1 - 15.5 mi

Top 41%
×4story building
+66ft-88ft

Overall

10895

Males

8455

M55-59

8455

25K→30K

15.5 - 18.6 mi

Top 65%
×9story building
+181ft-148ft

Overall

17236

Males

11011

M55-59

11011

30K→20M

18.6 - 20.0 mi

Top 76%
×5story building
+64ft-50ft

Overall

20269

Males

12236

M55-59

12236

20M→21M

20.0 - 21.0 mi

Top 74%
×8story building
+106ft-24ft

Overall

19681

Males

11902

M55-59

11902

21M→35K

21.0 - 21.8 mi

Top 80%
×7story building
+17ft-86ft

Overall

21381

Males

12650

M55-59

12650

35K→23M

21.8 - 23.0 mi

Top 90%
×5story building
+23ft-63ft

Overall

23950

Males

13830

M55-59

13830

23M→24M

23.0 - 24.0 mi

Top 92%
×6story building
+12ft-82ft

Overall

24567

Males

14073

M55-59

14073

24M→40K

24.0 - 24.9 mi

Top 95%
×1story
+6ft-20ft

Overall

25164

Males

14377

M55-59

14377

40K→25.2M

24.9 - 25.2 mi

Top 96%
×1story
+13ft-16ft

Overall

25501

Males

14543

M55-59

14543

25.2M→Finish

25.2 - 26.2 mi

Top 97%
×2story building
+22ft-21ft

Overall

25693

Males

14643

M55-59

14643

Passing Analysis

Category:
Athletes Passed
575
Passed By
9410
Net Change
-8836
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#9037
5K → 10K111658-547#9037#9584
10K → 15K175159+16#9584#9568
15K → 20K150122+28#9568#9540
20K → Half1645-29#9540#9569
Half → 25K76282-206#9569#9775
25K → 30K91519-1511#9775#11286
30K → 20M61030-1024#11286#12310
20M → 21M13656-643#12310#12953
21M → 35K5509-504#12953#13457
35K → 23M21324-1322#13457#14779
23M → 24M8904-896#14779#15675
24M → 40K3951-948#15675#16623
40K → 25.2M1392-391#16623#17014
25.2M → Finish0859-859#17014#17873
TOTALS5759410-8836
📊

Passing Visuals

Category:
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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