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BOSTON MARATHON 2023

Casey Colby

Bib: 3845•M

CA

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 25%
Gender (Male)
#0 / 15176
Top 38%
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
21:25
Rank: #5512
Start → 5K
21:25 | 6:54/mi
10K· 6.21 mi
42:22
Rank: #5107 (+405)
5K → 10K
20:57 | 6:45/mi
15K· 9.32 mi
1:03:30
Rank: #5116 (-9)
10K → 15K
21:08 | 6:48/mi
20K· 12.43 mi
1:24:54
Rank: #5157 (-41)
15K → 20K
21:24 | 6:53/mi
Half· 13.11 mi
1:29:32
Rank: #5160 (-3)
20K → Half
4:38 | 6:47/mi
25K· 15.53 mi
1:47:23
Rank: #5669 (-509)
Half → 25K
17:51 | 7:22/mi
30K· 18.64 mi
2:11:16
Rank: #6070 (-401)
25K → 30K
23:53 | 7:41/mi
20M
2:21:53
Rank: #6207 (-137)
30K → 20M
10:37 | 7:49/mi
21M
2:29:56
Rank: #6224 (-17)
20M → 21M
8:03 | 8:03/mi
35K· 21.75 mi
2:35:42
Rank: #6303 (-79)
21M → 35K
5:46 | 7:42/mi
23M
2:45:34
Rank: #6393 (-90)
35K → 23M
9:52 | 7:53/mi
24M
2:53:20
Rank: #6474 (-81)
23M → 24M
7:46 | 7:46/mi
40K· 24.85 mi
3:00:06
Rank: #6506 (-32)
24M → 40K
6:46 | 7:55/mi
25.2M
3:03:04
Rank: #6537 (-31)
40K → 25.2M
2:58 | 8:36/mi
Finish· 26.22 mi
3:10:57
Rank: #6634 (-97)
25.2M → Finish
7:53 | 7:44/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:29:32
Pace6:50 /mi
2nd Half
Distance13.11 mi
Time1:41:25
Pace7:44 /mi
📊Positive Split: 13.3% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:22:3121:256:5421:25
6:54
-
10K
6.21 mi10:43:2842:226:4920:57
6:45
-0:09
15K
9.32 mi11:04:361:03:306:4921:08
6:48
+0:03
20K
12.43 mi11:26:001:24:546:5021:24
6:53
+0:05
Half
13.11 mi11:30:381:29:326:504:38
6:47
-0:06
25K
15.53 mi11:48:291:47:236:5517:51
7:22
+0:35
30K
18.64 mi12:12:222:11:167:0323:53
7:41
+0:19
20M
20.00 mi12:22:592:21:537:0610:37
7:49
+0:08
21M
21.00 mi12:31:022:29:567:088:03
8:03
+0:14
35K
21.75 mi12:36:482:35:427:105:46
7:42
-0:21
23M
23.00 mi12:46:402:45:347:129:52
7:53
+0:11
24M
24.00 mi12:54:262:53:207:137:46
7:46
-0:07
40K
24.85 mi13:01:123:00:067:156:46
7:55
+0:09
25.2M
25.20 mi13:04:103:03:047:162:58
8:36
+0:41
Finish
26.22 mi13:12:033:10:577:177:53
7:44
-0:52

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

6:45 /mi

Average Pace

7:17 /mi

Slowest Pace

8:36 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:47:23

56% of race

Time at Steady Pace

1:12:33

38% of race

Time at Slower Pace

11:01

6% of race

Average Pace: 7:17 /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 mi10:22:3121:256:5421:25
6:54
#5512
10K
6.21 mi10:43:2842:226:4920:57
6:45
#5107
15K
9.32 mi11:04:361:03:306:4921:08
6:48
#5116
20K
12.43 mi11:26:001:24:546:5021:24
6:53
#5157
Half
13.11 mi11:30:381:29:326:504:38
6:47
#5160
25K
15.53 mi11:48:291:47:236:5517:51
7:22
#5669
30K
18.64 mi12:12:222:11:167:0323:53
7:41
#6070
20M
20.00 mi12:22:592:21:537:0610:37
7:49
#6207
21M
21.00 mi12:31:022:29:567:088:03
8:03
#6224
35K
21.75 mi12:36:482:35:427:105:46
7:42
#6303
23M
23.00 mi12:46:402:45:347:129:52
7:53
#6393
24M
24.00 mi12:54:262:53:207:137:46
7:46
#6474
40K
24.85 mi13:01:123:00:067:156:46
7:55
#6506
25.2M
25.20 mi13:04:103:03:047:162:58
8:36
#6537
Finish
26.22 mi13:12:033:10:577:177:53
7:44
#6634
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi5512508550855162(Top 19%)4779(Top 31%)4779(Top 90%)
10K6.21 mi3.10 mi5107+4054734+3514734+3514767(Top 18%)4431(Top 29%)4431(Top 84%)
15K9.32 mi3.11 mi5116-94745-114745-115162(Top 19%)4779(Top 31%)4779(Top 90%)
20K12.43 mi3.11 mi5157-414781-364781-365262(Top 20%)4863(Top 32%)4863(Top 92%)
Half13.11 mi0.68 mi5160-34788-74788-75244(Top 20%)4854(Top 32%)4854(Top 92%)
25K15.53 mi2.42 mi5669-5095213-4255213-4257684(Top 29%)6595(Top 43%)6595(Top 125%)
30K18.64 mi3.11 mi6070-4015517-3045517-3048530(Top 32%)6998(Top 46%)6998(Top 132%)
20M20.00 mi1.36 mi6207-1375608-915608-918918(Top 33%)7132(Top 47%)7132(Top 135%)
21M21.00 mi1.00 mi6224-17560856087635(Top 29%)6261(Top 41%)6261(Top 118%)
35K21.75 mi0.75 mi6303-795669-615669-619923(Top 37%)7577(Top 50%)7577(Top 143%)
23M23.00 mi1.25 mi6393-905718-495718-498918(Top 33%)6918(Top 46%)6918(Top 131%)
24M24.00 mi1.00 mi6474-815762-445762-449491(Top 36%)7139(Top 47%)7139(Top 135%)
40K24.85 mi0.85 mi6506-325772-105772-109396(Top 35%)7023(Top 46%)7023(Top 133%)
25.2M25.20 mi0.35 mi6537-315786-145786-1410074(Top 38%)7308(Top 48%)7308(Top 138%)
Finish26.22 mi1.02 mi6634-975840-545840-5410177(Top 38%)7377(Top 49%)7377(Top 140%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 19%
×21stories
+97ft-345ft

Overall

5162

Males

4779

M18-39

4779

5K→10K

3.1 - 6.2 mi

Top 18%
×5stories
+79ft-138ft

Overall

4767

Males

4431

M18-39

4431

10K→15K

6.2 - 9.3 mi

Top 19%
×3stories
+67ft-78ft

Overall

5162

Males

4779

M18-39

4779

15K→20K

9.3 - 12.4 mi

Top 20%
×5stories
+106ft-86ft

Overall

5262

Males

4863

M18-39

4863

20K→Half

12.4 - 13.1 mi

Top 20%
×2stories
+19ft-37ft

Overall

5244

Males

4854

M18-39

4854

Half→25K

13.1 - 15.5 mi

Top 29%
×4stories
+66ft-88ft

Overall

7684

Males

6595

M18-39

6595

25K→30K

15.5 - 18.6 mi

Top 32%
×9stories
+181ft-148ft

Overall

8530

Males

6998

M18-39

6998

30K→20M

18.6 - 20.0 mi

Top 33%
×5stories
+64ft-50ft

Overall

8918

Males

7132

M18-39

7132

20M→21M

20.0 - 21.0 mi

Top 29%
×8stories
+106ft-24ft

Overall

7635

Males

6261

M18-39

6261

21M→35K

21.0 - 21.8 mi

Top 37%
×7stories
+17ft-86ft

Overall

9923

Males

7577

M18-39

7577

35K→23M

21.8 - 23.0 mi

Top 33%
×5stories
+23ft-63ft

Overall

8918

Males

6918

M18-39

6918

23M→24M

23.0 - 24.0 mi

Top 36%
×6stories
+12ft-82ft

Overall

9491

Males

7139

M18-39

7139

24M→40K

24.0 - 24.9 mi

Top 35%
×1story
+6ft-20ft

Overall

9396

Males

7023

M18-39

7023

40K→25.2M

24.9 - 25.2 mi

Top 38%
×1story
+13ft-16ft

Overall

10074

Males

7308

M18-39

7308

25.2M→Finish

25.2 - 26.2 mi

Top 38%
×2stories
+22ft-21ft

Overall

10177

Males

7377

M18-39

7377

Passing Analysis

Category:
Athletes Passed
1004
Passed By
2126
Net Change
-1122
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#5512
5K → 10K46459+405#5512#5107
10K → 15K111120-9#5107#5116
15K → 20K94135-41#5116#5157
20K → Half2225-3#5157#5160
Half → 25K16525-509#5160#5669
25K → 30K43444-401#5669#6070
30K → 20M28165-137#6070#6207
20M → 21M4966-17#6207#6224
21M → 35K1493-79#6224#6303
35K → 23M43133-90#6303#6393
23M → 24M39120-81#6393#6474
24M → 40K3769-32#6474#6506
40K → 25.2M1748-31#6506#6537
25.2M → Finish27124-97#6537#6634
TOTALS10042126-1122
📊

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