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BOSTON MARATHON 2023

Justin Marsh

Bib: 5237•M

NH

0:00
0:00
/ mi
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Overall
#0 / 26622
Gender (Male)
#0 / 15176
Division (M18-39)
#0 / 5285
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
21:48
Rank: #6351
Start → 5K
21:48 | 7:01/mi
10K· 6.21 mi
43:28
Rank: #6475 (-124)
5K → 10K
21:40 | 6:58/mi
15K· 9.32 mi
1:09:28
Rank: #9638 (-3163)
10K → 15K
26:00 | 8:22/mi
20K· 12.43 mi
1:55:31
Rank: #21491 (-11853)
15K → 20K
46:03 | 14:49/mi
Half· 13.11 mi
2:02:20
Rank: #21608 (-117)
20K → Half
6:49 | 9:59/mi
25K· 15.53 mi
2:26:21
Rank: #21645 (-37)
Half → 25K
24:01 | 9:54/mi
30K· 18.64 mi
2:57:15
Rank: #21508 (+137)
25K → 30K
30:54 | 9:57/mi
20M
3:10:45
Rank: #21409 (+99)
30K → 20M
13:30 | 9:56/mi
21M
3:20:42
Rank: #21215 (+194)
20M → 21M
9:57 | 9:57/mi
35K· 21.75 mi
3:27:30
Rank: #21111 (+104)
21M → 35K
6:48 | 9:05/mi
23M
3:39:04
Rank: #20871 (+240)
35K → 23M
11:34 | 9:14/mi
24M
3:47:56
Rank: #20726 (+145)
23M → 24M
8:52 | 8:52/mi
40K· 24.85 mi
3:55:34
Rank: #20572 (+154)
24M → 40K
7:38 | 8:56/mi
25.2M
3:58:53
Rank: #20482 (+90)
40K → 25.2M
3:19 | 9:37/mi
Finish· 26.22 mi
4:08:35
Rank: #20468 (+14)
25.2M → Finish
9:42 | 9:31/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time2:02:20
Pace9:20 /mi
2nd Half
Distance13.11 mi
Time2:06:15
Pace9:38 /mi
📊Positive Split: 3.2% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:24:3921:487:0121:48
7:01
-
10K
6.21 mi10:46:1943:287:0021:40
6:58
-0:03
15K
9.32 mi11:12:191:09:287:2726:00
8:22
+1:24
20K
12.43 mi11:58:221:55:319:1846:03
14:49
+6:27
Half
13.11 mi12:05:112:02:209:206:49
9:59
-4:50
25K
15.53 mi12:29:122:26:219:2524:01
9:54
-0:05
30K
18.64 mi13:00:062:57:159:3130:54
9:57
+0:03
20M
20.00 mi13:13:363:10:459:3213:30
9:56
-0:01
21M
21.00 mi13:23:333:20:429:339:57
9:57
+0:01
35K
21.75 mi13:30:213:27:309:326:48
9:05
-0:52
23M
23.00 mi13:41:553:39:049:3111:34
9:14
+0:09
24M
24.00 mi13:50:473:47:569:308:52
8:52
-0:22
40K
24.85 mi13:58:253:55:349:297:38
8:56
+0:04
25.2M
25.20 mi14:01:443:58:539:293:19
9:37
+0:41
Finish
26.22 mi14:11:264:08:359:299:42
9:31
-0:06

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

6:58 /mi

Average Pace

9:29 /mi

Slowest Pace

14:49 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:09:28

28% of race

Time at Steady Pace

2:13:04

54% of race

Time at Slower Pace

46:03

19% of race

Average Pace: 9:29 /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 mi10:24:3921:487:0121:48
7:01
#6351
10K
6.21 mi10:46:1943:287:0021:40
6:58
#6475
15K
9.32 mi11:12:191:09:287:2726:00
8:22
#9638
20K
12.43 mi11:58:221:55:319:1846:03
14:49
#21491
Half
13.11 mi12:05:112:02:209:206:49
9:59
#21608
25K
15.53 mi12:29:122:26:219:2524:01
9:54
#21645
30K
18.64 mi13:00:062:57:159:3130:54
9:57
#21508
20M
20.00 mi13:13:363:10:459:3213:30
9:56
#21409
21M
21.00 mi13:23:333:20:429:339:57
9:57
#21215
35K
21.75 mi13:30:213:27:309:326:48
9:05
#21111
23M
23.00 mi13:41:553:39:049:3111:34
9:14
#20871
24M
24.00 mi13:50:473:47:569:308:52
8:52
#20726
40K
24.85 mi13:58:253:55:349:297:38
8:56
#20572
25.2M
25.20 mi14:01:443:58:539:293:19
9:37
#20482
Finish
26.22 mi14:11:264:08:359:299:42
9:31
#20468
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi63515780578016962(Top 64%)11058(Top 73%)11058(Top 209%)
10K6.21 mi3.10 mi6475-1245851-715851-716657(Top 25%)5979(Top 39%)5979(Top 113%)
15K9.32 mi3.11 mi9638-31637949-20987949-209816962(Top 64%)11058(Top 73%)11058(Top 209%)
20K12.43 mi3.11 mi21491-1185312923-497412923-497426589(Top 100%)15158(Top 100%)15158(Top 287%)
Half13.11 mi0.68 mi21608-11712974-5112974-5123239(Top 87%)13725(Top 90%)13725(Top 260%)
25K15.53 mi2.42 mi21645-3713000-2613000-2621997(Top 83%)13135(Top 87%)13135(Top 249%)
30K18.64 mi3.11 mi21508+13712927+7312927+7320867(Top 78%)12578(Top 83%)12578(Top 238%)
20M20.00 mi1.36 mi21409+9912869+5812869+5820278(Top 76%)12245(Top 81%)12245(Top 232%)
21M21.00 mi1.00 mi21215+19412761+10812761+10817852(Top 67%)11170(Top 74%)11170(Top 211%)
35K21.75 mi0.75 mi21111+10412706+5512706+5518273(Top 69%)11275(Top 74%)11275(Top 213%)
23M23.00 mi1.25 mi20871+24012587+11912587+11917241(Top 65%)10802(Top 71%)10802(Top 204%)
24M24.00 mi1.00 mi20726+14512514+7312514+7316576(Top 62%)10448(Top 69%)10448(Top 198%)
40K24.85 mi0.85 mi20572+15412433+8112433+8115751(Top 59%)10036(Top 66%)10036(Top 190%)
25.2M25.20 mi0.35 mi20482+9012397+3612397+3615735(Top 59%)10023(Top 66%)10023(Top 190%)
Finish26.22 mi1.02 mi20468+1412379+1812379+1820188(Top 76%)12057(Top 79%)12057(Top 228%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 64%
×21stories
+97ft-345ft

Overall

16962

Males

11058

M18-39

11058

5K→10K

3.1 - 6.2 mi

Top 25%
×5stories
+79ft-138ft

Overall

6657

Males

5979

M18-39

5979

10K→15K

6.2 - 9.3 mi

Top 64%
×3stories
+67ft-78ft

Overall

16962

Males

11058

M18-39

11058

15K→20K

9.3 - 12.4 mi

Top 100%
×5stories
+106ft-86ft

Overall

26589

Males

15158

M18-39

15158

20K→Half

12.4 - 13.1 mi

Top 87%
×2stories
+19ft-37ft

Overall

23239

Males

13725

M18-39

13725

Half→25K

13.1 - 15.5 mi

Top 83%
×4stories
+66ft-88ft

Overall

21997

Males

13135

M18-39

13135

25K→30K

15.5 - 18.6 mi

Top 78%
×9stories
+181ft-148ft

Overall

20867

Males

12578

M18-39

12578

30K→20M

18.6 - 20.0 mi

Top 76%
×5stories
+64ft-50ft

Overall

20278

Males

12245

M18-39

12245

20M→21M

20.0 - 21.0 mi

Top 67%
×8stories
+106ft-24ft

Overall

17852

Males

11170

M18-39

11170

21M→35K

21.0 - 21.8 mi

Top 69%
×7stories
+17ft-86ft

Overall

18273

Males

11275

M18-39

11275

35K→23M

21.8 - 23.0 mi

Top 65%
×5stories
+23ft-63ft

Overall

17241

Males

10802

M18-39

10802

23M→24M

23.0 - 24.0 mi

Top 62%
×6stories
+12ft-82ft

Overall

16576

Males

10448

M18-39

10448

24M→40K

24.0 - 24.9 mi

Top 59%
×1story
+6ft-20ft

Overall

15751

Males

10036

M18-39

10036

40K→25.2M

24.9 - 25.2 mi

Top 59%
×1story
+13ft-16ft

Overall

15735

Males

10023

M18-39

10023

25.2M→Finish

25.2 - 26.2 mi

Top 76%
×2stories
+22ft-21ft

Overall

20188

Males

12057

M18-39

12057

Passing Analysis

Category:
Athletes Passed
1531
Passed By
15646
Net Change
-14117
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#6351
5K → 10K131255-124#6351#6475
10K → 15K23165-3163#6475#9638
15K → 20K011851-11853#9638#21491
20K → Half5122-117#21491#21608
Half → 25K92129-37#21608#21645
25K → 30K19760+137#21645#21508
30K → 20M12425+99#21508#21409
20M → 21M1951+194#21409#21215
21M → 35K1062+104#21215#21111
35K → 23M2411+240#21111#20871
23M → 24M1450+145#20871#20726
24M → 40K1540+154#20726#20572
40K → 25.2M900+90#20572#20482
25.2M → Finish4935+14#20482#20468
TOTALS153115646-14117
📊

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