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BOSTON MARATHON 2023

John Zerby

Bib: 25610•M

MA

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

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
9:03/mi
28:06
↑ 97↓ 3451.5%
10K· 6.21 mi
8:49/mi
55:30
↑ 79↓ 1380.4%
15K· 9.32 mi
8:38/mi
1:22:20
↑ 67↓ 78
20K· 12.43 mi
8:41/mi
1:49:18
↑ 106↓ 860.1%
Half· 13.11 mi
8:34/mi
1:55:09
↑ 19↓ 370.5%
25K· 15.53 mi
8:35/mi
2:15:57
↑ 66↓ 880.2%
30K· 18.64 mi
8:26/mi
2:42:08
↑ 181↓ 1480.2%
20M
8:14/mi
2:53:19
↑ 64↓ 500.2%
21M
8:46/mi
3:02:05
↑ 106↓ 241.6%
35K· 21.75 mi
8:00/mi
3:08:04
↑ 17↓ 861.7%
23M
8:30/mi
3:18:42
↑ 23↓ 630.6%
24M
8:22/mi
3:27:04
↓ 821.3%
40K· 24.85 mi
8:38/mi
3:34:27
↓ 200.3%
25.2M
9:23/mi
3:37:41
↑ 13↓ 160.2%
Finish· 26.22 mi
8:48/mi
3:46:39
↑ 22↓ 21

The Course

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Half Splits

1st Half· via Half
Distance13.11 mi
Time1:55:09
Pace8:47 /mi
2nd Half✓ Faster
Distance13.11 mi
Time1:51:30
Pace8:30 /mi
📊Negative Split: 3.2% faster second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:48:3228:069:0328:06
9:03
-
10K
6.21 mi12:15:5655:308:5627:24
8:49
-0:14
15K
9.32 mi12:42:461:22:208:5026:50
8:38
-0:11
20K
12.43 mi13:09:441:49:188:4826:58
8:41
+0:03
Half
13.11 mi13:15:351:55:098:475:51
8:34
-0:07
25K
15.53 mi13:36:232:15:578:4520:48
8:35
+0:01
30K
18.64 mi14:02:342:42:088:4226:11
8:26
-0:09
20M
20.00 mi14:13:452:53:198:4011:11
8:14
-0:12
21M
21.00 mi14:22:313:02:058:408:46
8:46
+0:32
35K
21.75 mi14:28:303:08:048:395:59
8:00
-0:46
23M
23.00 mi14:39:083:18:428:3810:38
8:30
+0:30
24M
24.00 mi14:47:303:27:048:388:22
8:22
-0:08
40K
24.85 mi14:54:533:34:278:387:23
8:38
+0:16
25.2M
25.20 mi14:58:073:37:418:383:14
9:23
+0:45
Finish
26.22 mi15:07:053:46:398:398:58
8:48
-0:35

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

8:00 /mi

Average Pace

8:39 /mi

Slowest Pace

9:23 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:47:55

74% of race

Time at Steady Pace

58:44

26% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 8:39 /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 mi11:48:3228:069:0328:06
9:03
#20641
10K
6.21 mi12:15:5655:308:5627:24
8:49
#20352
15K
9.32 mi12:42:461:22:208:5026:50
8:38
#19781
20K
12.43 mi13:09:441:49:188:4826:58
8:41
#19296
Half
13.11 mi13:15:351:55:098:475:51
8:34
#19238
25K
15.53 mi13:36:232:15:578:4520:48
8:35
#18856
30K
18.64 mi14:02:342:42:088:4226:11
8:26
#17957
20M
20.00 mi14:13:452:53:198:4011:11
8:14
#17520
21M
21.00 mi14:22:313:02:058:408:46
8:46
#17208
35K
21.75 mi14:28:303:08:048:395:59
8:00
#17037
23M
23.00 mi14:39:083:18:428:3810:38
8:30
#16818
24M
24.00 mi14:47:303:27:048:388:22
8:22
#16670
40K
24.85 mi14:54:533:34:278:387:23
8:38
#16571
25.2M
25.20 mi14:58:073:37:418:383:14
9:23
#16532
Finish
26.22 mi15:07:053:46:398:398:58
8:48
#16539
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi20641124251242518650(Top 70%)11739(Top 77%)11739(Top 222%)
10K6.21 mi3.10 mi20352+28912379+4612379+4620025(Top 75%)12287(Top 81%)12287(Top 232%)
15K9.32 mi3.11 mi19781+57112151+22812151+22818650(Top 70%)11739(Top 77%)11739(Top 222%)
20K12.43 mi3.11 mi19296+48511973+17811973+17817977(Top 68%)11456(Top 75%)11456(Top 217%)
Half13.11 mi0.68 mi19238+5811956+1711956+1718113(Top 68%)11519(Top 76%)11519(Top 218%)
25K15.53 mi2.42 mi18856+38211795+16111795+16116670(Top 63%)10832(Top 71%)10832(Top 205%)
30K18.64 mi3.11 mi17957+89911397+39811397+39813856(Top 52%)9598(Top 63%)9598(Top 182%)
20M20.00 mi1.36 mi17520+43711206+19111206+19111883(Top 45%)8668(Top 57%)8668(Top 164%)
21M21.00 mi1.00 mi17208+31211069+13711069+13712061(Top 45%)8619(Top 57%)8619(Top 163%)
35K21.75 mi0.75 mi17037+17110995+7410995+7412110(Top 45%)8619(Top 57%)8619(Top 163%)
23M23.00 mi1.25 mi16818+21910887+10810887+10813163(Top 49%)8996(Top 59%)8996(Top 170%)
24M24.00 mi1.00 mi16670+14810805+8210805+8213635(Top 51%)9159(Top 60%)9159(Top 173%)
40K24.85 mi0.85 mi16571+9910743+6210743+6214156(Top 53%)9314(Top 61%)9314(Top 176%)
25.2M25.20 mi0.35 mi16532+3910719+2410719+2414535(Top 55%)9491(Top 63%)9491(Top 180%)
Finish26.22 mi1.02 mi16539-710712+710712+717019(Top 64%)10615(Top 70%)10615(Top 201%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 70%
×21story building
+97ft-345ft

Overall

18650

Males

11739

M18-39

11739

5K→10K

3.1 - 6.2 mi

Top 75%
×5story building
+79ft-138ft

Overall

20025

Males

12287

M18-39

12287

10K→15K

6.2 - 9.3 mi

Top 70%
×3story building
+67ft-78ft

Overall

18650

Males

11739

M18-39

11739

15K→20K

9.3 - 12.4 mi

Top 68%
×5story building
+106ft-86ft

Overall

17977

Males

11456

M18-39

11456

20K→Half

12.4 - 13.1 mi

Top 68%
×2story building
+19ft-37ft

Overall

18113

Males

11519

M18-39

11519

Half→25K

13.1 - 15.5 mi

Top 63%
×4story building
+66ft-88ft

Overall

16670

Males

10832

M18-39

10832

25K→30K

15.5 - 18.6 mi

Top 52%
×9story building
+181ft-148ft

Overall

13856

Males

9598

M18-39

9598

30K→20M

18.6 - 20.0 mi

Top 45%
×5story building
+64ft-50ft

Overall

11883

Males

8668

M18-39

8668

20M→21M

20.0 - 21.0 mi

Top 45%
×8story building
+106ft-24ft

Overall

12061

Males

8619

M18-39

8619

21M→35K

21.0 - 21.8 mi

Top 45%
×7story building
+17ft-86ft

Overall

12110

Males

8619

M18-39

8619

35K→23M

21.8 - 23.0 mi

Top 49%
×5story building
+23ft-63ft

Overall

13163

Males

8996

M18-39

8996

23M→24M

23.0 - 24.0 mi

Top 51%
×6story building
+12ft-82ft

Overall

13635

Males

9159

M18-39

9159

24M→40K

24.0 - 24.9 mi

Top 53%
×1story
+6ft-20ft

Overall

14156

Males

9314

M18-39

9314

40K→25.2M

24.9 - 25.2 mi

Top 55%
×1story
+13ft-16ft

Overall

14535

Males

9491

M18-39

9491

25.2M→Finish

25.2 - 26.2 mi

Top 64%
×2story building
+22ft-21ft

Overall

17019

Males

10615

M18-39

10615

Passing Analysis

Category:
Athletes Passed
4457
Passed By
355
Net Change
+4102
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#20641
5K → 10K482193+289#20641#20352
10K → 15K60635+571#20352#19781
15K → 20K50116+485#19781#19296
20K → Half602+58#19296#19238
Half → 25K3842+382#19238#18856
25K → 30K9023+899#18856#17957
30K → 20M4370+437#17957#17520
20M → 21M3142+312#17520#17208
21M → 35K1721+171#17208#17037
35K → 23M2234+219#17037#16818
23M → 24M15810+148#16818#16670
24M → 40K11516+99#16670#16571
40K → 25.2M5314+39#16571#16532
25.2M → Finish5057-7#16532#16539
TOTALS4457355+4102
📊

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