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BOSTON MARATHON 2023

John Loftus

Bib: 4517•M

MA

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 8%
Gender (Male)
#0 / 15176
Top 13%
Division (M18-39)
#0 / 5285
Top 29%
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
20:09
Rank: #2198
Start → 5K
20:09 | 6:29/mi
10K· 6.21 mi
39:57
Rank: #2128 (+70)
5K → 10K
19:48 | 6:22/mi
15K· 9.32 mi
1:00:46
Rank: #2639 (-511)
10K → 15K
20:49 | 6:42/mi
20K· 12.43 mi
1:20:57
Rank: #2525 (+114)
15K → 20K
20:11 | 6:30/mi
Half· 13.11 mi
1:25:18
Rank: #2491 (+34)
20K → Half
4:21 | 6:23/mi
25K· 15.53 mi
1:40:44
Rank: #2334 (+157)
Half → 25K
15:26 | 6:22/mi
30K· 18.64 mi
2:00:45
Rank: #2100 (+234)
25K → 30K
20:01 | 6:27/mi
20M
2:09:29
Rank: #2012 (+88)
30K → 20M
8:44 | 6:26/mi
21M
2:16:01
Rank: #1900 (+112)
20M → 21M
6:32 | 6:32/mi
35K· 21.75 mi
2:20:35
Rank: #1842 (+58)
21M → 35K
4:34 | 6:06/mi
23M
2:28:49
Rank: #1805 (+37)
35K → 23M
8:14 | 6:35/mi
24M
2:35:27
Rank: #1829 (-24)
23M → 24M
6:38 | 6:38/mi
40K· 24.85 mi
2:41:19
Rank: #1858 (-29)
24M → 40K
5:52 | 6:52/mi
25.2M
2:43:59
Rank: #1884 (-26)
40K → 25.2M
2:40 | 7:44/mi
Finish· 26.22 mi
2:51:24
Rank: #2003 (-119)
25.2M → Finish
7:25 | 7:17/mi

The Course

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Half Splits

1st Half· via Half⚖️ Balanced
Distance13.11 mi
Time1:25:18
Pace6:30 /mi
2nd Half⚖️ Balanced
Distance13.11 mi
Time1:26:06
Pace6:34 /mi
📊Even Split: Consistent pacing between halves

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:21:5720:096:2920:09
6:29
-
10K
6.21 mi10:41:4539:576:2619:48
6:22
-0:07
15K
9.32 mi11:02:341:00:466:3120:49
6:42
+0:20
20K
12.43 mi11:22:451:20:576:3120:11
6:30
-0:12
Half
13.11 mi11:27:061:25:186:304:21
6:23
-0:07
25K
15.53 mi11:42:321:40:446:2915:26
6:22
-0:01
30K
18.64 mi12:02:332:00:456:2920:01
6:27
+0:05
20M
20.00 mi12:11:172:09:296:288:44
6:26
-0:01
21M
21.00 mi12:17:492:16:016:296:32
6:32
+0:06
35K
21.75 mi12:22:232:20:356:284:34
6:06
-0:26
23M
23.00 mi12:30:372:28:496:288:14
6:35
+0:29
24M
24.00 mi12:37:152:35:276:296:38
6:38
+0:03
40K
24.85 mi12:43:072:41:196:295:52
6:52
+0:14
25.2M
25.20 mi12:45:472:43:596:302:40
7:44
+0:52
Finish
26.22 mi12:53:122:51:246:337:25
7:17
-0:27

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

6:06 /mi

Average Pace

6:33 /mi

Slowest Pace

7:44 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

4:34

3% of race

Time at Steady Pace

2:10:04

76% of race

Time at Slower Pace

36:46

21% of race

Average Pace: 6:32 /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 mi10:21:5720:096:2920:09
6:29
#2198
10K
6.21 mi10:41:4539:576:2619:48
6:22
#2128
15K
9.32 mi11:02:341:00:466:3120:49
6:42
#2639
20K
12.43 mi11:22:451:20:576:3120:11
6:30
#2525
Half
13.11 mi11:27:061:25:186:304:21
6:23
#2491
25K
15.53 mi11:42:321:40:446:2915:26
6:22
#2334
30K
18.64 mi12:02:332:00:456:2920:01
6:27
#2100
20M
20.00 mi12:11:172:09:296:288:44
6:26
#2012
21M
21.00 mi12:17:492:16:016:296:32
6:32
#1900
35K
21.75 mi12:22:232:20:356:284:34
6:06
#1842
23M
23.00 mi12:30:372:28:496:288:14
6:35
#1805
24M
24.00 mi12:37:152:35:276:296:38
6:38
#1829
40K
24.85 mi12:43:072:41:196:295:52
6:52
#1858
25.2M
25.20 mi12:45:472:43:596:302:40
7:44
#1884
Finish
26.22 mi12:53:122:51:246:337:25
7:17
#2003
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi2198209720974104(Top 15%)3850(Top 25%)3850(Top 73%)
10K6.21 mi3.10 mi2128+702037+602037+602097(Top 8%)2008(Top 13%)2008(Top 38%)
15K9.32 mi3.11 mi2639-5112520-4832520-4834104(Top 15%)3850(Top 25%)3850(Top 73%)
20K12.43 mi3.11 mi2525+1142416+1042416+1042261(Top 8%)2166(Top 14%)2166(Top 41%)
Half13.11 mi0.68 mi2491+342386+302386+302103(Top 8%)2019(Top 13%)2019(Top 38%)
25K15.53 mi2.42 mi2334+1572239+1472239+1471589(Top 6%)1523(Top 10%)1523(Top 29%)
30K18.64 mi3.11 mi2100+2342014+2252014+2251357(Top 5%)1299(Top 9%)1299(Top 25%)
20M20.00 mi1.36 mi2012+881928+861928+861224(Top 5%)1166(Top 8%)1166(Top 22%)
21M21.00 mi1.00 mi1900+1121817+1111817+111730(Top 3%)689(Top 5%)689(Top 13%)
35K21.75 mi0.75 mi1842+581761+561761+56969(Top 4%)921(Top 6%)921(Top 17%)
23M23.00 mi1.25 mi1805+371726+351726+351696(Top 6%)1610(Top 11%)1610(Top 30%)
24M24.00 mi1.00 mi1829-241749-231749-232715(Top 10%)2524(Top 17%)2524(Top 48%)
40K24.85 mi0.85 mi1858-291777-281777-283081(Top 12%)2825(Top 19%)2825(Top 53%)
25.2M25.20 mi0.35 mi1884-261801-241801-244928(Top 19%)4205(Top 28%)4205(Top 80%)
Finish26.22 mi1.02 mi2003-1191919-1181919-1186912(Top 26%)5495(Top 36%)5495(Top 104%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 15%
×21stories
+97ft-345ft

Overall

4104

Males

3850

M18-39

3850

5K→10K

3.1 - 6.2 mi

Top 8%
×5stories
+79ft-138ft

Overall

2097

Males

2008

M18-39

2008

10K→15K

6.2 - 9.3 mi

Top 15%
×3stories
+67ft-78ft

Overall

4104

Males

3850

M18-39

3850

15K→20K

9.3 - 12.4 mi

Top 8%
×5stories
+106ft-86ft

Overall

2261

Males

2166

M18-39

2166

20K→Half

12.4 - 13.1 mi

Top 8%
×2stories
+19ft-37ft

Overall

2103

Males

2019

M18-39

2019

Half→25K

13.1 - 15.5 mi

Top 6%
×4stories
+66ft-88ft

Overall

1589

Males

1523

M18-39

1523

25K→30K

15.5 - 18.6 mi

Top 5%
×9stories
+181ft-148ft

Overall

1357

Males

1299

M18-39

1299

30K→20M

18.6 - 20.0 mi

Top 5%
×5stories
+64ft-50ft

Overall

1224

Males

1166

M18-39

1166

20M→21M

20.0 - 21.0 mi

Top 3%
×8stories
+106ft-24ft

Overall

730

Males

689

M18-39

689

21M→35K

21.0 - 21.8 mi

Top 4%
×7stories
+17ft-86ft

Overall

969

Males

921

M18-39

921

35K→23M

21.8 - 23.0 mi

Top 6%
×5stories
+23ft-63ft

Overall

1696

Males

1610

M18-39

1610

23M→24M

23.0 - 24.0 mi

Top 10%
×6stories
+12ft-82ft

Overall

2715

Males

2524

M18-39

2524

24M→40K

24.0 - 24.9 mi

Top 12%
×1story
+6ft-20ft

Overall

3081

Males

2825

M18-39

2825

40K→25.2M

24.9 - 25.2 mi

Top 19%
×1story
+13ft-16ft

Overall

4928

Males

4205

M18-39

4205

25.2M→Finish

25.2 - 26.2 mi

Top 26%
×2stories
+22ft-21ft

Overall

6912

Males

5495

M18-39

5495

Passing Analysis

Category:
Athletes Passed
1079
Passed By
884
Net Change
+195
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#2198
5K → 10K15282+70#2198#2128
10K → 15K2513-511#2128#2639
15K → 20K13016+114#2639#2525
20K → Half384+34#2525#2491
Half → 25K1581+157#2491#2334
25K → 30K2395+234#2334#2100
30K → 20M902+88#2100#2012
20M → 21M1131+112#2012#1900
21M → 35K580+58#1900#1842
35K → 23M5619+37#1842#1805
23M → 24M1640-24#1805#1829
24M → 40K1746-29#1829#1858
40K → 25.2M430-26#1858#1884
25.2M → Finish6125-119#1884#2003
TOTALS1079884+195
📊

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