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BOSTON MARATHON 2023

Justin Grissom

Bib: 3591•M

TX

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 (M40-44)
#0 / 2241
Top 24%
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
20:53
Rank: #3860
Start → 5K
20:53 | 6:43/mi
10K· 6.21 mi
41:09
Rank: #3326 (+534)
5K → 10K
20:16 | 6:31/mi
15K· 9.32 mi
1:01:36
Rank: #3257 (+69)
10K → 15K
20:27 | 6:35/mi
20K· 12.43 mi
1:22:32
Rank: #3391 (-134)
15K → 20K
20:56 | 6:44/mi
Half· 13.11 mi
1:26:59
Rank: #3354 (+37)
20K → Half
4:27 | 6:31/mi
25K· 15.53 mi
1:43:18
Rank: #3357 (-3)
Half → 25K
16:19 | 6:44/mi
30K· 18.64 mi
2:04:53
Rank: #3433 (-76)
25K → 30K
21:35 | 6:57/mi
20M
2:14:22
Rank: #3442 (-9)
30K → 20M
9:29 | 6:59/mi
21M
2:21:41
Rank: #3429 (+13)
20M → 21M
7:19 | 7:19/mi
35K· 21.75 mi
2:26:48
Rank: #3444 (-15)
21M → 35K
5:07 | 6:50/mi
23M
2:35:39
Rank: #3472 (-28)
35K → 23M
8:51 | 7:04/mi
24M
2:42:23
Rank: #3451 (+21)
23M → 24M
6:44 | 6:44/mi
40K· 24.85 mi
2:48:27
Rank: #3474 (-23)
24M → 40K
6:04 | 7:06/mi
25.2M
2:51:05
Rank: #3475 (-1)
40K → 25.2M
2:38 | 7:38/mi
Finish· 26.22 mi
2:58:13
Rank: #3558 (-83)
25.2M → Finish
7:08 | 7:00/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:26:59
Pace6:38 /mi
2nd Half
Distance13.11 mi
Time1:31:14
Pace6:58 /mi
📊Positive Split: 4.9% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:22:1120:536:4320:53
6:43
-
10K
6.21 mi10:42:2741:096:3720:16
6:31
-0:12
15K
9.32 mi11:02:541:01:366:3720:27
6:35
+0:04
20K
12.43 mi11:23:501:22:326:3820:56
6:44
+0:09
Half
13.11 mi11:28:171:26:596:384:27
6:31
-0:13
25K
15.53 mi11:44:361:43:186:3916:19
6:44
+0:13
30K
18.64 mi12:06:112:04:536:4221:35
6:57
+0:13
20M
20.00 mi12:15:402:14:226:439:29
6:59
+0:02
21M
21.00 mi12:22:592:21:416:457:19
7:19
+0:20
35K
21.75 mi12:28:062:26:486:455:07
6:50
-0:29
23M
23.00 mi12:36:572:35:396:468:51
7:04
+0:14
24M
24.00 mi12:43:412:42:236:466:44
6:44
-0:20
40K
24.85 mi12:49:452:48:276:476:04
7:06
+0:22
25.2M
25.20 mi12:52:232:51:056:472:38
7:38
+0:32
Finish
26.22 mi12:59:312:58:136:487:08
7:00
-0:38

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

6:31 /mi

Average Pace

6:48 /mi

Slowest Pace

7:38 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:48:16

94% of race

Time at Steady Pace

9:57

6% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 6:48 /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 mi10:22:1120:536:4320:53
6:43
#3860
10K
6.21 mi10:42:2741:096:3720:16
6:31
#3326
15K
9.32 mi11:02:541:01:366:3720:27
6:35
#3257
20K
12.43 mi11:23:501:22:326:3820:56
6:44
#3391
Half
13.11 mi11:28:171:26:596:384:27
6:31
#3354
25K
15.53 mi11:44:361:43:186:3916:19
6:44
#3357
30K
18.64 mi12:06:112:04:536:4221:35
6:57
#3433
20M
20.00 mi12:15:402:14:226:439:29
6:59
#3442
21M
21.00 mi12:22:592:21:416:457:19
7:19
#3429
35K
21.75 mi12:28:062:26:486:455:07
6:50
#3444
23M
23.00 mi12:36:572:35:396:468:51
7:04
#3472
24M
24.00 mi12:43:412:42:236:466:44
6:44
#3451
40K
24.85 mi12:49:452:48:276:476:04
7:06
#3474
25.2M
25.20 mi12:52:232:51:056:472:38
7:38
#3475
Finish
26.22 mi12:59:312:58:136:487:08
7:00
#3558
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM40-44Seg. OverallSeg. MalesSeg. M40-44
5K3.11 mi3.11 mi3860362636263160(Top 12%)3009(Top 20%)3009(Top 134%)
10K6.21 mi3.10 mi3326+5343150+4763150+4762936(Top 11%)2806(Top 18%)2806(Top 125%)
15K9.32 mi3.11 mi3257+693096+543096+543160(Top 12%)3009(Top 20%)3009(Top 134%)
20K12.43 mi3.11 mi3391-1343217-1213217-1213862(Top 15%)3642(Top 24%)3642(Top 163%)
Half13.11 mi0.68 mi3354+373187+303187+302960(Top 11%)2835(Top 19%)2835(Top 127%)
25K15.53 mi2.42 mi3357-33191-43191-43601(Top 14%)3396(Top 22%)3396(Top 152%)
30K18.64 mi3.11 mi3433-763251-603251-603977(Top 15%)3716(Top 24%)3716(Top 166%)
20M20.00 mi1.36 mi3442-93257-63257-63888(Top 15%)3616(Top 24%)3616(Top 161%)
21M21.00 mi1.00 mi3429+133247+103247+103684(Top 14%)3415(Top 23%)3415(Top 152%)
35K21.75 mi0.75 mi3444-153261-143261-144398(Top 17%)4016(Top 26%)4016(Top 179%)
23M23.00 mi1.25 mi3472-283284-233284-234119(Top 15%)3775(Top 25%)3775(Top 168%)
24M24.00 mi1.00 mi3451+213262+223262+223285(Top 12%)3040(Top 20%)3040(Top 136%)
40K24.85 mi0.85 mi3474-233282-203282-204322(Top 16%)3838(Top 25%)3838(Top 171%)
25.2M25.20 mi0.35 mi3475-13283-13283-14490(Top 17%)3903(Top 26%)3903(Top 174%)
Finish26.22 mi1.02 mi3558-833349-663349-665171(Top 19%)4379(Top 29%)4379(Top 195%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 12%
×21stories
+97ft-345ft

Overall

3160

Males

3009

M40-44

3009

5K→10K

3.1 - 6.2 mi

Top 11%
×5stories
+79ft-138ft

Overall

2936

Males

2806

M40-44

2806

10K→15K

6.2 - 9.3 mi

Top 12%
×3stories
+67ft-78ft

Overall

3160

Males

3009

M40-44

3009

15K→20K

9.3 - 12.4 mi

Top 15%
×5stories
+106ft-86ft

Overall

3862

Males

3642

M40-44

3642

20K→Half

12.4 - 13.1 mi

Top 11%
×2stories
+19ft-37ft

Overall

2960

Males

2835

M40-44

2835

Half→25K

13.1 - 15.5 mi

Top 14%
×4stories
+66ft-88ft

Overall

3601

Males

3396

M40-44

3396

25K→30K

15.5 - 18.6 mi

Top 15%
×9stories
+181ft-148ft

Overall

3977

Males

3716

M40-44

3716

30K→20M

18.6 - 20.0 mi

Top 15%
×5stories
+64ft-50ft

Overall

3888

Males

3616

M40-44

3616

20M→21M

20.0 - 21.0 mi

Top 14%
×8stories
+106ft-24ft

Overall

3684

Males

3415

M40-44

3415

21M→35K

21.0 - 21.8 mi

Top 17%
×7stories
+17ft-86ft

Overall

4398

Males

4016

M40-44

4016

35K→23M

21.8 - 23.0 mi

Top 15%
×5stories
+23ft-63ft

Overall

4119

Males

3775

M40-44

3775

23M→24M

23.0 - 24.0 mi

Top 12%
×6stories
+12ft-82ft

Overall

3285

Males

3040

M40-44

3040

24M→40K

24.0 - 24.9 mi

Top 16%
×1story
+6ft-20ft

Overall

4322

Males

3838

M40-44

3838

40K→25.2M

24.9 - 25.2 mi

Top 17%
×1story
+13ft-16ft

Overall

4490

Males

3903

M40-44

3903

25.2M→Finish

25.2 - 26.2 mi

Top 19%
×2stories
+22ft-21ft

Overall

5171

Males

4379

M40-44

4379

Passing Analysis

Category:
Athletes Passed
1255
Passed By
953
Net Change
+302
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#3860
5K → 10K57440+534#3860#3326
10K → 15K12960+69#3326#3257
15K → 20K49183-134#3257#3391
20K → Half436+37#3391#3354
Half → 25K7477-3#3354#3357
25K → 30K66142-76#3357#3433
30K → 20M5463-9#3433#3442
20M → 21M6451+13#3442#3429
21M → 35K2540-15#3429#3444
35K → 23M5280-28#3444#3472
23M → 24M4827+21#3472#3451
24M → 40K3356-23#3451#3474
40K → 25.2M1920-1#3474#3475
25.2M → Finish25108-83#3475#3558
TOTALS1255953+302
📊

Passing Visuals

Category:

📈Position Graph

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🎨Heatmap Timeline

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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