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BOSTON MARATHON 2023

Ondrej Blaha

Bib: 1542•M

CT

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
7:01/mi
21:49
↑ 97↓ 3451.5%
10K· 6.21 mi
6:47/mi
42:52
↑ 79↓ 1380.4%
15K· 9.32 mi
6:39/mi
1:03:31
↑ 67↓ 78
20K· 12.43 mi
6:39/mi
1:24:12
↑ 106↓ 860.1%
Half· 13.11 mi
6:34/mi
1:28:41
↑ 19↓ 370.5%
25K· 15.53 mi
6:31/mi
1:44:29
↑ 66↓ 880.2%
30K· 18.64 mi
13:19/mi
2:25:50
↑ 181↓ 1480.2%
20M
12:18/mi
2:42:33
↑ 64↓ 500.2%
21M
10:40/mi
2:53:13
↑ 106↓ 241.6%
35K· 21.75 mi
8:37/mi
2:59:40
↑ 17↓ 861.7%
23M
11:08/mi
3:13:36
↑ 23↓ 630.6%
24M
9:26/mi
3:23:02
↓ 821.3%
40K· 24.85 mi
8:39/mi
3:30:26
↓ 200.3%
25.2M
8:27/mi
3:33:21
↑ 13↓ 160.2%
Finish· 26.22 mi
7:38/mi
3:41:08
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:28:41
Pace6:46 /mi
2nd Half
Distance13.11 mi
Time2:12:27
Pace10:06 /mi
📊Positive Split: 49.4% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:25:2621:497:0121:49
7:01
-
10K
6.21 mi10:46:2942:526:5421:03
6:47
-0:14
15K
9.32 mi11:07:081:03:316:4920:39
6:39
-0:08
20K
12.43 mi11:27:491:24:126:4720:41
6:39
0:00
Half
13.11 mi11:32:181:28:416:464:29
6:34
-0:05
25K
15.53 mi11:48:061:44:296:4415:48
6:31
-0:03
30K
18.64 mi12:29:272:25:507:4941:21
13:19
+6:48
20M
20.00 mi12:46:102:42:338:0816:43
12:18
-1:01
21M
21.00 mi12:56:502:53:138:1510:40
10:40
-1:38
35K
21.75 mi13:03:172:59:408:166:27
8:37
-2:03
23M
23.00 mi13:17:133:13:368:2513:56
11:08
+2:31
24M
24.00 mi13:26:393:23:028:289:26
9:26
-1:42
40K
24.85 mi13:34:033:30:268:287:24
8:39
-0:47
25.2M
25.20 mi13:36:583:33:218:282:55
8:27
-0:12
Finish
26.22 mi13:44:453:41:088:267:47
7:38
-0:49

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

8:26 /mi

Slowest Pace

13:19 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:44:29

47% of race

Time at Steady Pace

33:59

15% of race

Time at Slower Pace

1:22:40

37% of race

Average Pace: 8:26 /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 mi10:25:2621:497:0121:49
7:01
#6391
10K
6.21 mi10:46:2942:526:5421:03
6:47
#5814
15K
9.32 mi11:07:081:03:316:4920:39
6:39
#5134
20K
12.43 mi11:27:491:24:126:4720:41
6:39
#4606
Half
13.11 mi11:32:181:28:416:464:29
6:34
#4512
25K
15.53 mi11:48:061:44:296:4415:48
6:31
#4026
30K
18.64 mi12:29:272:25:507:4941:21
13:19
#11806
20M
20.00 mi12:46:102:42:338:0816:43
12:18
#14059
21M
21.00 mi12:56:502:53:138:1510:40
10:40
#14531
35K
21.75 mi13:03:172:59:408:166:27
8:37
#14595
23M
23.00 mi13:17:133:13:368:2513:56
11:08
#15413
24M
24.00 mi13:26:393:23:028:289:26
9:26
#15597
40K
24.85 mi13:34:033:30:268:287:24
8:39
#15555
25.2M
25.20 mi13:36:583:33:218:282:55
8:27
#15459
Finish
26.22 mi13:44:453:41:088:267:47
7:38
#15217
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi6391581058103682(Top 14%)3473(Top 23%)3473(Top 66%)
10K6.21 mi3.10 mi5814+5775336+4745336+4745073(Top 19%)4696(Top 31%)4696(Top 89%)
15K9.32 mi3.11 mi5134+6804761+5754761+5753682(Top 14%)3473(Top 23%)3473(Top 66%)
20K12.43 mi3.11 mi4606+5284296+4654296+4653247(Top 12%)3084(Top 20%)3084(Top 58%)
Half13.11 mi0.68 mi4512+944216+804216+803296(Top 12%)3146(Top 21%)3146(Top 60%)
25K15.53 mi2.42 mi4026+4863788+4283788+4282263(Top 9%)2171(Top 14%)2171(Top 41%)
30K18.64 mi3.11 mi11806-77808920-51328920-513225639(Top 96%)14701(Top 97%)14701(Top 278%)
20M20.00 mi1.36 mi14059-22539838-9189838-91824539(Top 92%)14157(Top 93%)14157(Top 268%)
21M21.00 mi1.00 mi14531-47210002-16410002-16420040(Top 75%)12061(Top 79%)12061(Top 228%)
35K21.75 mi0.75 mi14595-6410018-1610018-1615943(Top 60%)10266(Top 68%)10266(Top 194%)
23M23.00 mi1.25 mi15413-81810285-26710285-26722581(Top 85%)13190(Top 87%)13190(Top 250%)
24M24.00 mi1.00 mi15597-18410337-5210337-5218954(Top 71%)11509(Top 76%)11509(Top 218%)
40K24.85 mi0.85 mi15555+4210316+2110316+2114255(Top 54%)9354(Top 62%)9354(Top 177%)
25.2M25.20 mi0.35 mi15459+9610269+4710269+479261(Top 35%)6921(Top 46%)6921(Top 131%)
Finish26.22 mi1.02 mi15217+24210164+10510164+1059551(Top 36%)7057(Top 47%)7057(Top 134%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 14%
×21story building
+97ft-345ft

Overall

3682

Males

3473

M18-39

3473

5K→10K

3.1 - 6.2 mi

Top 19%
×5story building
+79ft-138ft

Overall

5073

Males

4696

M18-39

4696

10K→15K

6.2 - 9.3 mi

Top 14%
×3story building
+67ft-78ft

Overall

3682

Males

3473

M18-39

3473

15K→20K

9.3 - 12.4 mi

Top 12%
×5story building
+106ft-86ft

Overall

3247

Males

3084

M18-39

3084

20K→Half

12.4 - 13.1 mi

Top 12%
×2story building
+19ft-37ft

Overall

3296

Males

3146

M18-39

3146

Half→25K

13.1 - 15.5 mi

Top 9%
×4story building
+66ft-88ft

Overall

2263

Males

2171

M18-39

2171

25K→30K

15.5 - 18.6 mi

Top 96%
×9story building
+181ft-148ft

Overall

25639

Males

14701

M18-39

14701

30K→20M

18.6 - 20.0 mi

Top 92%
×5story building
+64ft-50ft

Overall

24539

Males

14157

M18-39

14157

20M→21M

20.0 - 21.0 mi

Top 75%
×8story building
+106ft-24ft

Overall

20040

Males

12061

M18-39

12061

21M→35K

21.0 - 21.8 mi

Top 60%
×7story building
+17ft-86ft

Overall

15943

Males

10266

M18-39

10266

35K→23M

21.8 - 23.0 mi

Top 85%
×5story building
+23ft-63ft

Overall

22581

Males

13190

M18-39

13190

23M→24M

23.0 - 24.0 mi

Top 71%
×6story building
+12ft-82ft

Overall

18954

Males

11509

M18-39

11509

24M→40K

24.0 - 24.9 mi

Top 54%
×1story
+6ft-20ft

Overall

14255

Males

9354

M18-39

9354

40K→25.2M

24.9 - 25.2 mi

Top 35%
×1story
+13ft-16ft

Overall

9261

Males

6921

M18-39

6921

25.2M→Finish

25.2 - 26.2 mi

Top 36%
×2story building
+22ft-21ft

Overall

9551

Males

7057

M18-39

7057

Passing Analysis

Category:
Athletes Passed
2895
Passed By
11719
Net Change
-8826
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#6391
5K → 10K60730+577#6391#5814
10K → 15K6811+680#5814#5134
15K → 20K5291+528#5134#4606
20K → Half962+94#4606#4512
Half → 25K4860+486#4512#4026
25K → 30K07778-7780#4026#11806
30K → 20M22255-2253#11806#14059
20M → 21M11483-472#14059#14531
21M → 35K2387-64#14531#14595
35K → 23M7825-818#14595#15413
23M → 24M29213-184#15413#15597
24M → 40K8240+42#15597#15555
40K → 25.2M971+96#15555#15459
25.2M → Finish2453+242#15459#15217
TOTALS289511719-8826
📊

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