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BOSTON MARATHON 2023

Nathan Shelub

Bib: 5864•M

CA

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Top 18%
Gender (Male)
#0 / 15176
Top 29%
Masters (Masters Men)
#0 / 9891
Top 15%
Division (M40-44)
#0 / 2241
Top 37%
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
6:49/mi
21:12
↑ 97↓ 3451.5%
10K· 6.21 mi
6:49/mi
42:23
↑ 79↓ 1380.4%
15K· 9.32 mi
6:47/mi
1:03:29
↑ 67↓ 78
20K· 12.43 mi
6:47/mi
1:24:35
↑ 106↓ 860.1%
Half· 13.11 mi
6:46/mi
1:29:12
↑ 19↓ 370.5%
25K· 15.53 mi
6:49/mi
1:45:43
↑ 66↓ 880.2%
30K· 18.64 mi
6:55/mi
2:07:13
↑ 181↓ 1480.2%
20M
7:07/mi
2:16:53
↑ 64↓ 500.2%
21M
7:45/mi
2:24:38
↑ 106↓ 241.6%
35K· 21.75 mi
7:14/mi
2:30:03
↑ 17↓ 861.7%
23M
7:21/mi
2:39:15
↑ 23↓ 630.6%
24M
7:20/mi
2:46:35
↓ 821.3%
40K· 24.85 mi
7:28/mi
2:52:58
↓ 200.3%
25.2M
8:10/mi
2:55:47
↑ 13↓ 160.2%
Finish· 26.22 mi
7:11/mi
3:03:06
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:29:12
Pace6:48 /mi
2nd Half
Distance13.11 mi
Time1:33:54
Pace7:10 /mi
📊Positive Split: 5.3% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:24:3621:126:4921:12
6:49
-
10K
6.21 mi10:45:4742:236:4921:11
6:49
0:00
15K
9.32 mi11:06:531:03:296:4921:06
6:47
-0:02
20K
12.43 mi11:27:591:24:356:4821:06
6:47
0:00
Half
13.11 mi11:32:361:29:126:484:37
6:46
-0:01
25K
15.53 mi11:49:071:45:436:4816:31
6:49
+0:03
30K
18.64 mi12:10:372:07:136:4921:30
6:55
+0:06
20M
20.00 mi12:20:172:16:536:519:40
7:07
+0:12
21M
21.00 mi12:28:022:24:386:537:45
7:45
+0:38
35K
21.75 mi12:33:272:30:036:545:25
7:14
-0:31
23M
23.00 mi12:42:392:39:156:559:12
7:21
+0:07
24M
24.00 mi12:49:592:46:356:567:20
7:20
-0:01
40K
24.85 mi12:56:222:52:586:586:23
7:28
+0:08
25.2M
25.20 mi12:59:112:55:476:592:49
8:10
+0:42
Finish
26.22 mi13:06:303:03:066:597:19
7:11
-0:59

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

6:46 /mi

Average Pace

6:59 /mi

Slowest Pace

8:10 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:07:13

69% of race

Time at Steady Pace

22:24

12% of race

Time at Slower Pace

33:29

18% of race

Average Pace: 6:59 /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 mi10:24:3621:126:4921:12
6:49
#4897
10K
6.21 mi10:45:4742:236:4921:11
6:49
#5124
15K
9.32 mi11:06:531:03:296:4921:06
6:47
#5096
20K
12.43 mi11:27:591:24:356:4821:06
6:47
#4906
Half
13.11 mi11:32:361:29:126:484:37
6:46
#4906
25K
15.53 mi11:49:071:45:436:4816:31
6:49
#4754
30K
18.64 mi12:10:372:07:136:4921:30
6:55
#4530
20M
20.00 mi12:20:172:16:536:519:40
7:07
#4536
21M
21.00 mi12:28:022:24:386:537:45
7:45
#4638
35K
21.75 mi12:33:272:30:036:545:25
7:14
#4714
23M
23.00 mi12:42:392:39:156:559:12
7:21
#4745
24M
24.00 mi12:49:592:46:356:567:20
7:20
#4812
40K
24.85 mi12:56:222:52:586:586:23
7:28
#4836
25.2M
25.20 mi12:59:112:55:476:592:49
8:10
#4856
Finish
26.22 mi13:06:303:03:066:597:19
7:11
#4854
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM40-44Seg. OverallSeg. MalesSeg. M40-44
5K3.11 mi3.11 mi4897455245525020(Top 19%)4660(Top 31%)4660(Top 208%)
10K6.21 mi3.10 mi5124-2274748-1964748-1965464(Top 21%)5034(Top 33%)5034(Top 225%)
15K9.32 mi3.11 mi5096+284729+194729+195020(Top 19%)4660(Top 31%)4660(Top 208%)
20K12.43 mi3.11 mi4906+1904568+1614568+1614371(Top 16%)4081(Top 27%)4081(Top 182%)
Half13.11 mi0.68 mi49064564+44564+44977(Top 19%)4609(Top 30%)4609(Top 206%)
25K15.53 mi2.42 mi4754+1524427+1374427+1374268(Top 16%)3993(Top 26%)3993(Top 178%)
30K18.64 mi3.11 mi4530+2244230+1974230+1973800(Top 14%)3564(Top 23%)3564(Top 159%)
20M20.00 mi1.36 mi4536-64229+14229+14677(Top 18%)4282(Top 28%)4282(Top 191%)
21M21.00 mi1.00 mi4638-1024319-904319-905871(Top 22%)5098(Top 34%)5098(Top 227%)
35K21.75 mi0.75 mi4714-764386-674386-676720(Top 25%)5706(Top 38%)5706(Top 255%)
23M23.00 mi1.25 mi4745-314410-244410-245538(Top 21%)4861(Top 32%)4861(Top 217%)
24M24.00 mi1.00 mi4812-674458-484458-486560(Top 25%)5450(Top 36%)5450(Top 243%)
40K24.85 mi0.85 mi4836-244469-114469-116452(Top 24%)5298(Top 35%)5298(Top 236%)
25.2M25.20 mi0.35 mi4856-204481-124481-127393(Top 28%)5793(Top 38%)5793(Top 259%)
Finish26.22 mi1.02 mi4854+24474+74474+76253(Top 23%)5092(Top 34%)5092(Top 227%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 19%
×21story building
+97ft-345ft

Overall

5020

Males

4660

M40-44

4660

5K→10K

3.1 - 6.2 mi

Top 21%
×5story building
+79ft-138ft

Overall

5464

Males

5034

M40-44

5034

10K→15K

6.2 - 9.3 mi

Top 19%
×3story building
+67ft-78ft

Overall

5020

Males

4660

M40-44

4660

15K→20K

9.3 - 12.4 mi

Top 16%
×5story building
+106ft-86ft

Overall

4371

Males

4081

M40-44

4081

20K→Half

12.4 - 13.1 mi

Top 19%
×2story building
+19ft-37ft

Overall

4977

Males

4609

M40-44

4609

Half→25K

13.1 - 15.5 mi

Top 16%
×4story building
+66ft-88ft

Overall

4268

Males

3993

M40-44

3993

25K→30K

15.5 - 18.6 mi

Top 14%
×9story building
+181ft-148ft

Overall

3800

Males

3564

M40-44

3564

30K→20M

18.6 - 20.0 mi

Top 18%
×5story building
+64ft-50ft

Overall

4677

Males

4282

M40-44

4282

20M→21M

20.0 - 21.0 mi

Top 22%
×8story building
+106ft-24ft

Overall

5871

Males

5098

M40-44

5098

21M→35K

21.0 - 21.8 mi

Top 25%
×7story building
+17ft-86ft

Overall

6720

Males

5706

M40-44

5706

35K→23M

21.8 - 23.0 mi

Top 21%
×5story building
+23ft-63ft

Overall

5538

Males

4861

M40-44

4861

23M→24M

23.0 - 24.0 mi

Top 25%
×6story building
+12ft-82ft

Overall

6560

Males

5450

M40-44

5450

24M→40K

24.0 - 24.9 mi

Top 24%
×1story
+6ft-20ft

Overall

6452

Males

5298

M40-44

5298

40K→25.2M

24.9 - 25.2 mi

Top 28%
×1story
+13ft-16ft

Overall

7393

Males

5793

M40-44

5793

25.2M→Finish

25.2 - 26.2 mi

Top 23%
×2story building
+22ft-21ft

Overall

6253

Males

5092

M40-44

5092

Passing Analysis

Category:
Athletes Passed
1223
Passed By
1180
Net Change
+43
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#4897
5K → 10K112339-227#4897#5124
10K → 15K128100+28#5124#5096
15K → 20K22131+190#5096#4906
20K → Half20200#4906#4906
Half → 25K18129+152#4906#4754
25K → 30K26339+224#4754#4530
30K → 20M6066-6#4530#4536
20M → 21M31133-102#4536#4638
21M → 35K26102-76#4638#4714
35K → 23M5990-31#4714#4745
23M → 24M2794-67#4745#4812
24M → 40K3458-24#4812#4836
40K → 25.2M1333-20#4836#4856
25.2M → Finish4846+2#4856#4854
TOTALS12231180+43
📊

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