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BOSTON MARATHON 2023

Corey Nislow

Bib: 12303•M

BC

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Gender (Male)
#0 / 15176
Masters (Masters Men)
#0 / 9891
Division (M55-59)
#0 / 1422
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
9:09/mi
28:25
↑ 97↓ 3451.5%
10K· 6.21 mi
8:18/mi
54:12
↑ 79↓ 1380.4%
15K· 9.32 mi
8:11/mi
1:19:36
↑ 67↓ 78
20K· 12.43 mi
8:20/mi
1:45:30
↑ 106↓ 860.1%
Half· 13.11 mi
7:52/mi
1:50:52
↑ 19↓ 370.5%
25K· 15.53 mi
8:16/mi
2:10:55
↑ 66↓ 880.2%
30K· 18.64 mi
8:46/mi
2:38:09
↑ 181↓ 1480.2%
20M
8:25/mi
2:49:35
↑ 64↓ 500.2%
21M
8:55/mi
2:58:30
↑ 106↓ 241.6%
35K· 21.75 mi
9:05/mi
3:05:18
↑ 17↓ 861.7%
23M
8:24/mi
3:15:49
↑ 23↓ 630.6%
24M
8:01/mi
3:23:50
↓ 821.3%
40K· 24.85 mi
8:14/mi
3:30:52
↓ 200.3%
25.2M
8:51/mi
3:33:55
↑ 13↓ 160.2%
Finish· 26.22 mi
7:40/mi
3:41:44
↑ 22↓ 21

The Course

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Half Splits

1st Half· via Half⚖️ Balanced
Distance13.11 mi
Time1:50:52
Pace8:27 /mi
2nd Half⚖️ Balanced
Distance13.11 mi
Time1:50:52
Pace8:27 /mi
📊Even Split: Consistent pacing between halves

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:49:2428:259:0928:25
9:09
-
10K
6.21 mi12:15:1154:128:4325:47
8:18
-0:51
15K
9.32 mi12:40:351:19:368:3225:24
8:11
-0:07
20K
12.43 mi13:06:291:45:308:2925:54
8:20
+0:09
Half
13.11 mi13:11:511:50:528:275:22
7:52
-0:28
25K
15.53 mi13:31:542:10:558:2620:03
8:16
+0:24
30K
18.64 mi13:59:082:38:098:2927:14
8:46
+0:30
20M
20.00 mi14:10:342:49:358:2911:26
8:25
-0:21
21M
21.00 mi14:19:292:58:308:308:55
8:55
+0:30
35K
21.75 mi14:26:173:05:188:316:48
9:05
+0:10
23M
23.00 mi14:36:483:15:498:3110:31
8:24
-0:41
24M
24.00 mi14:44:493:23:508:308:01
8:01
-0:23
40K
24.85 mi14:51:513:30:528:297:02
8:14
+0:13
25.2M
25.20 mi14:54:543:33:558:293:03
8:51
+0:37
Finish
26.22 mi15:02:433:41:448:287:49
7:40
-1:11

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

7:40 /mi

Average Pace

8:28 /mi

Slowest Pace

9:09 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:27:19

66% of race

Time at Steady Pace

39:12

18% of race

Time at Slower Pace

35:13

16% of race

Average Pace: 8:27 /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 mi11:49:2428:259:0928:25
9:09
#21024
10K
6.21 mi12:15:1154:128:4325:47
8:18
#19239
15K
9.32 mi12:40:351:19:368:3225:24
8:11
#18102
20K
12.43 mi13:06:291:45:308:2925:54
8:20
#17478
Half
13.11 mi13:11:511:50:528:275:22
7:52
#17304
25K
15.53 mi13:31:542:10:558:2620:03
8:16
#16903
30K
18.64 mi13:59:082:38:098:2927:14
8:46
#16671
20M
20.00 mi14:10:342:49:358:2911:26
8:25
#16399
21M
21.00 mi14:19:292:58:308:308:55
8:55
#16192
35K
21.75 mi14:26:173:05:188:316:48
9:05
#16279
23M
23.00 mi14:36:483:15:498:3110:31
8:24
#16039
24M
24.00 mi14:44:493:23:508:308:01
8:01
#15833
40K
24.85 mi14:51:513:30:528:297:02
8:14
#15660
25.2M
25.20 mi14:54:543:33:558:293:03
8:51
#15611
Finish
26.22 mi15:02:433:41:448:287:49
7:40
#15377
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM55-59Seg. OverallSeg. MalesSeg. M55-59
5K3.11 mi3.11 mi21024126171261715683(Top 59%)10563(Top 70%)10563(Top 743%)
10K6.21 mi3.10 mi19239+178511915+70211915+70216908(Top 64%)11070(Top 73%)11070(Top 778%)
15K9.32 mi3.11 mi18102+113711495+42011495+42015683(Top 59%)10563(Top 70%)10563(Top 743%)
20K12.43 mi3.11 mi17478+62411253+24211253+24215832(Top 59%)10565(Top 70%)10565(Top 743%)
Half13.11 mi0.68 mi17304+17411178+7511178+7513290(Top 50%)9620(Top 63%)9620(Top 677%)
25K15.53 mi2.42 mi16903+40110986+19210986+19214725(Top 55%)10051(Top 66%)10051(Top 707%)
30K18.64 mi3.11 mi16671+23210861+12510861+12515850(Top 60%)10413(Top 69%)10413(Top 732%)
20M20.00 mi1.36 mi16399+27210732+12910732+12913094(Top 49%)9174(Top 60%)9174(Top 645%)
21M21.00 mi1.00 mi16192+20710636+9610636+9612926(Top 49%)9006(Top 59%)9006(Top 633%)
35K21.75 mi0.75 mi16279-8710666-3010666-3018236(Top 68%)11238(Top 74%)11238(Top 790%)
23M23.00 mi1.25 mi16039+24010536+13010536+13012571(Top 47%)8726(Top 57%)8726(Top 614%)
24M24.00 mi1.00 mi15833+20610434+10210434+10211355(Top 43%)8086(Top 53%)8086(Top 569%)
40K24.85 mi0.85 mi15660+17310359+7510359+7511537(Top 43%)8103(Top 53%)8103(Top 570%)
25.2M25.20 mi0.35 mi15611+4910332+2710332+2711567(Top 43%)8081(Top 53%)8081(Top 568%)
Finish26.22 mi1.02 mi15377+23410225+10710225+1079788(Top 37%)7180(Top 47%)7180(Top 505%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 59%
×21story building
+97ft-345ft

Overall

15683

Males

10563

M55-59

10563

5K→10K

3.1 - 6.2 mi

Top 64%
×5story building
+79ft-138ft

Overall

16908

Males

11070

M55-59

11070

10K→15K

6.2 - 9.3 mi

Top 59%
×3story building
+67ft-78ft

Overall

15683

Males

10563

M55-59

10563

15K→20K

9.3 - 12.4 mi

Top 59%
×5story building
+106ft-86ft

Overall

15832

Males

10565

M55-59

10565

20K→Half

12.4 - 13.1 mi

Top 50%
×2story building
+19ft-37ft

Overall

13290

Males

9620

M55-59

9620

Half→25K

13.1 - 15.5 mi

Top 55%
×4story building
+66ft-88ft

Overall

14725

Males

10051

M55-59

10051

25K→30K

15.5 - 18.6 mi

Top 60%
×9story building
+181ft-148ft

Overall

15850

Males

10413

M55-59

10413

30K→20M

18.6 - 20.0 mi

Top 49%
×5story building
+64ft-50ft

Overall

13094

Males

9174

M55-59

9174

20M→21M

20.0 - 21.0 mi

Top 49%
×8story building
+106ft-24ft

Overall

12926

Males

9006

M55-59

9006

21M→35K

21.0 - 21.8 mi

Top 68%
×7story building
+17ft-86ft

Overall

18236

Males

11238

M55-59

11238

35K→23M

21.8 - 23.0 mi

Top 47%
×5story building
+23ft-63ft

Overall

12571

Males

8726

M55-59

8726

23M→24M

23.0 - 24.0 mi

Top 43%
×6story building
+12ft-82ft

Overall

11355

Males

8086

M55-59

8086

24M→40K

24.0 - 24.9 mi

Top 43%
×1story
+6ft-20ft

Overall

11537

Males

8103

M55-59

8103

40K→25.2M

24.9 - 25.2 mi

Top 43%
×1story
+13ft-16ft

Overall

11567

Males

8081

M55-59

8081

25.2M→Finish

25.2 - 26.2 mi

Top 37%
×2story building
+22ft-21ft

Overall

9788

Males

7180

M55-59

7180

Passing Analysis

Category:
Athletes Passed
5889
Passed By
242
Net Change
+5647
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#21024
5K → 10K179510+1785#21024#19239
10K → 15K11469+1137#19239#18102
15K → 20K63612+624#18102#17478
20K → Half1751+174#17478#17304
Half → 25K4076+401#17304#16903
25K → 30K28856+232#16903#16671
30K → 20M2775+272#16671#16399
20M → 21M2136+207#16399#16192
21M → 35K24111-87#16192#16279
35K → 23M2477+240#16279#16039
23M → 24M2104+206#16039#15833
24M → 40K1785+173#15833#15660
40K → 25.2M512+49#15660#15611
25.2M → Finish2428+234#15611#15377
TOTALS5889242+5647
📊

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