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BOSTON MARATHON 2023

Jeffrey Blazek

Bib: 10527•M

NY

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Top 37%
Gender (Male)
#0 / 15176
Masters (Masters Men)
#0 / 9891
Top 41%
Division (M45-49)
#0 / 2252
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
7:15/mi
22:32
↑ 97↓ 3451.5%
10K· 6.21 mi
7:13/mi
44:57
↑ 79↓ 1380.4%
15K· 9.32 mi
7:25/mi
1:07:58
↑ 67↓ 78
20K· 12.43 mi
7:34/mi
1:31:28
↑ 106↓ 860.1%
Half· 13.11 mi
7:26/mi
1:36:32
↑ 19↓ 370.5%
25K· 15.53 mi
7:41/mi
1:55:09
↑ 66↓ 880.2%
30K· 18.64 mi
8:00/mi
2:20:00
↑ 181↓ 1480.2%
20M
8:06/mi
2:31:00
↑ 64↓ 500.2%
21M
8:49/mi
2:39:49
↑ 106↓ 241.6%
35K· 21.75 mi
7:49/mi
2:45:40
↑ 17↓ 861.7%
23M
8:15/mi
2:56:00
↑ 23↓ 630.6%
24M
8:02/mi
3:04:02
↓ 821.3%
40K· 24.85 mi
8:09/mi
3:11:00
↓ 200.3%
25.2M
9:14/mi
3:14:11
↑ 13↓ 160.2%
Finish· 26.22 mi
8:16/mi
3:22:36
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:36:32
Pace7:22 /mi
2nd Half
Distance13.11 mi
Time1:46:04
Pace8:05 /mi
📊Positive Split: 9.9% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:48:5922:327:1522:32
7:15
-
10K
6.21 mi11:11:2444:577:1422:25
7:13
-0:02
15K
9.32 mi11:34:251:07:587:1823:01
7:25
+0:12
20K
12.43 mi11:57:551:31:287:2223:30
7:34
+0:09
Half
13.11 mi12:02:591:36:327:225:04
7:26
-0:08
25K
15.53 mi12:21:361:55:097:2518:37
7:41
+0:15
30K
18.64 mi12:46:272:20:007:3124:51
8:00
+0:19
20M
20.00 mi12:57:272:31:007:3311:00
8:06
+0:06
21M
21.00 mi13:06:162:39:497:378:49
8:49
+0:43
35K
21.75 mi13:12:072:45:407:375:51
7:49
-1:00
23M
23.00 mi13:22:272:56:007:3910:20
8:15
+0:26
24M
24.00 mi13:30:293:04:027:408:02
8:02
-0:13
40K
24.85 mi13:37:273:11:007:416:58
8:09
+0:07
25.2M
25.20 mi13:40:383:14:117:423:11
9:14
+1:05
Finish
26.22 mi13:49:033:22:367:448:25
8:16
-0:58

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

7:13 /mi

Average Pace

7:44 /mi

Slowest Pace

9:14 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:55:09

57% of race

Time at Steady Pace

1:15:27

37% of race

Time at Slower Pace

12:00

6% of race

Average Pace: 7:44 /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 mi10:48:5922:327:1522:32
7:15
#7815
10K
6.21 mi11:11:2444:577:1422:25
7:13
#7984
15K
9.32 mi11:34:251:07:587:1823:01
7:25
#8406
20K
12.43 mi11:57:551:31:287:2223:30
7:34
#8697
Half
13.11 mi12:02:591:36:327:225:04
7:26
#8735
25K
15.53 mi12:21:361:55:097:2518:37
7:41
#8916
30K
18.64 mi12:46:272:20:007:3124:51
8:00
#9233
20M
20.00 mi12:57:272:31:007:3311:00
8:06
#9363
21M
21.00 mi13:06:162:39:497:378:49
8:49
#9509
35K
21.75 mi13:12:072:45:407:375:51
7:49
#9541
23M
23.00 mi13:22:272:56:007:3910:20
8:15
#9626
24M
24.00 mi13:30:293:04:027:408:02
8:02
#9674
40K
24.85 mi13:37:273:11:007:416:58
8:09
#9707
25.2M
25.20 mi13:40:383:14:117:423:11
9:14
#9769
Finish
26.22 mi13:49:033:22:367:448:25
8:16
#9918
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM45-49Seg. OverallSeg. MalesSeg. M45-49
5K3.11 mi3.11 mi7815685268529402(Top 35%)7806(Top 51%)7806(Top 347%)
10K6.21 mi3.10 mi7984-1696959-1076959-1078215(Top 31%)7093(Top 47%)7093(Top 315%)
15K9.32 mi3.11 mi8406-4227216-2577216-2579402(Top 35%)7806(Top 51%)7806(Top 347%)
20K12.43 mi3.11 mi8697-2917374-1587374-1589802(Top 37%)7963(Top 52%)7963(Top 354%)
Half13.11 mi0.68 mi8735-387393-197393-199590(Top 36%)7871(Top 52%)7871(Top 350%)
25K15.53 mi2.42 mi8916-1817488-957488-9510120(Top 38%)8054(Top 53%)8054(Top 358%)
30K18.64 mi3.11 mi9233-3177648-1607648-16010883(Top 41%)8285(Top 55%)8285(Top 368%)
20M20.00 mi1.36 mi9363-1307694-467694-4610953(Top 41%)8225(Top 54%)8225(Top 365%)
21M21.00 mi1.00 mi9509-1467763-697763-6912331(Top 46%)8723(Top 57%)8723(Top 387%)
35K21.75 mi0.75 mi9541-327769-67769-610762(Top 40%)7985(Top 53%)7985(Top 355%)
23M23.00 mi1.25 mi9626-857783-147783-1411522(Top 43%)8237(Top 54%)8237(Top 366%)
24M24.00 mi1.00 mi9674-487788-57788-511443(Top 43%)8119(Top 53%)8119(Top 361%)
40K24.85 mi0.85 mi9707-337782+67782+610996(Top 41%)7835(Top 52%)7835(Top 348%)
25.2M25.20 mi0.35 mi9769-627793-117793-1113705(Top 51%)9073(Top 60%)9073(Top 403%)
Finish26.22 mi1.02 mi9918-1497849-567849-5613802(Top 52%)9143(Top 60%)9143(Top 406%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 35%
×21story building
+97ft-345ft

Overall

9402

Males

7806

M45-49

7806

5K→10K

3.1 - 6.2 mi

Top 31%
×5story building
+79ft-138ft

Overall

8215

Males

7093

M45-49

7093

10K→15K

6.2 - 9.3 mi

Top 35%
×3story building
+67ft-78ft

Overall

9402

Males

7806

M45-49

7806

15K→20K

9.3 - 12.4 mi

Top 37%
×5story building
+106ft-86ft

Overall

9802

Males

7963

M45-49

7963

20K→Half

12.4 - 13.1 mi

Top 36%
×2story building
+19ft-37ft

Overall

9590

Males

7871

M45-49

7871

Half→25K

13.1 - 15.5 mi

Top 38%
×4story building
+66ft-88ft

Overall

10120

Males

8054

M45-49

8054

25K→30K

15.5 - 18.6 mi

Top 41%
×9story building
+181ft-148ft

Overall

10883

Males

8285

M45-49

8285

30K→20M

18.6 - 20.0 mi

Top 41%
×5story building
+64ft-50ft

Overall

10953

Males

8225

M45-49

8225

20M→21M

20.0 - 21.0 mi

Top 46%
×8story building
+106ft-24ft

Overall

12331

Males

8723

M45-49

8723

21M→35K

21.0 - 21.8 mi

Top 40%
×7story building
+17ft-86ft

Overall

10762

Males

7985

M45-49

7985

35K→23M

21.8 - 23.0 mi

Top 43%
×5story building
+23ft-63ft

Overall

11522

Males

8237

M45-49

8237

23M→24M

23.0 - 24.0 mi

Top 43%
×6story building
+12ft-82ft

Overall

11443

Males

8119

M45-49

8119

24M→40K

24.0 - 24.9 mi

Top 41%
×1story
+6ft-20ft

Overall

10996

Males

7835

M45-49

7835

40K→25.2M

24.9 - 25.2 mi

Top 51%
×1story
+13ft-16ft

Overall

13705

Males

9073

M45-49

9073

25.2M→Finish

25.2 - 26.2 mi

Top 52%
×2story building
+22ft-21ft

Overall

13802

Males

9143

M45-49

9143

Passing Analysis

Category:
Athletes Passed
749*
Passed By
2852
Net Change
-2103
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#7815
5K → 10K152321-169#7815#7984
10K → 15K36458-422#7984#8406
15K → 20K59350-291#8406#8697
20K → Half1351-38#8697#8735
Half → 25K53234-181#8735#8916
25K → 30K91408-317#8916#9233
30K → 20M39169-130#9233#9363
20M → 21M51197-146#9363#9509
21M → 35K3971-32#9509#9541
35K → 23M68153-85#9541#9626
23M → 24M4795-48#9626#9674
24M → 40K44*77-33#9674#9707
40K → 25.2M2183-62#9707#9769
25.2M → Finish36*185-149#9769#9918
TOTALS749*2852-2103

* Includes athletes who did not complete a segment (DNF/DNQ).

📊

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