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BOSTON MARATHON 2023

Joshua Defronzo

Bib: 29463•M

RI

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

Start
0:00:00
Race begins
5K· 3.11 mi
30:08
Rank: #22645
Start → 5K
30:08 | 9:42/mi
10K· 6.21 mi
57:40
Rank: #21664 (+981)
5K → 10K
27:32 | 8:52/mi
15K· 9.32 mi
1:24:34
Rank: #20905 (+759)
10K → 15K
26:54 | 8:39/mi
20K· 12.43 mi
1:51:54
Rank: #20385 (+520)
15K → 20K
27:20 | 8:48/mi
Half· 13.11 mi
1:57:34
Rank: #20218 (+167)
20K → Half
5:40 | 8:18/mi
25K· 15.53 mi
2:18:17
Rank: #19629 (+589)
Half → 25K
20:43 | 8:33/mi
30K· 18.64 mi
2:45:03
Rank: #18850 (+779)
25K → 30K
26:46 | 8:37/mi
20M
2:57:00
Rank: #18605 (+245)
30K → 20M
11:57 | 8:48/mi
21M
3:05:53
Rank: #18285 (+320)
20M → 21M
8:53 | 8:53/mi
35K· 21.75 mi
3:11:46
Rank: #18046 (+239)
21M → 35K
5:53 | 7:52/mi
23M
3:22:20
Rank: #17754 (+292)
35K → 23M
10:34 | 8:26/mi
24M
3:30:42
Rank: #17574 (+180)
23M → 24M
8:22 | 8:22/mi
40K· 24.85 mi
3:38:07
Rank: #17452 (+122)
24M → 40K
7:25 | 8:40/mi
25.2M
3:41:08
Rank: #17352 (+100)
40K → 25.2M
3:01 | 8:45/mi
Finish· 26.22 mi
3:48:52
Rank: #17076 (+276)
25.2M → Finish
7:44 | 7:35/mi

The Course

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Half Splits

1st Half· via Half
Distance13.11 mi
Time1:57:34
Pace8:58 /mi
2nd Half✓ Faster
Distance13.11 mi
Time1:51:18
Pace8:29 /mi
📊Negative Split: 5.3% faster second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:49:5430:089:4230:08
9:42
-
10K
6.21 mi12:17:2657:409:1727:32
8:52
-0:50
15K
9.32 mi12:44:201:24:349:0426:54
8:39
-0:13
20K
12.43 mi13:11:401:51:549:0027:20
8:48
+0:09
Half
13.11 mi13:17:201:57:348:585:40
8:18
-0:30
25K
15.53 mi13:38:032:18:178:5420:43
8:33
+0:15
30K
18.64 mi14:04:492:45:038:5126:46
8:37
+0:04
20M
20.00 mi14:16:462:57:008:5111:57
8:48
+0:11
21M
21.00 mi14:25:393:05:538:518:53
8:53
+0:05
35K
21.75 mi14:31:323:11:468:495:53
7:52
-1:01
23M
23.00 mi14:42:063:22:208:4810:34
8:26
+0:34
24M
24.00 mi14:50:283:30:428:478:22
8:22
-0:04
40K
24.85 mi14:57:533:38:078:477:25
8:40
+0:18
25.2M
25.20 mi15:00:543:41:088:473:01
8:45
+0:05
Finish
26.22 mi15:08:383:48:528:447:44
7:35
-1:10

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

7:35 /mi

Average Pace

8:44 /mi

Slowest Pace

9:42 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

27:39

12% of race

Time at Steady Pace

2:42:12

71% of race

Time at Slower Pace

39:01

17% of race

Average Pace: 8:44 /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 mi11:49:5430:089:4230:08
9:42
#22645
10K
6.21 mi12:17:2657:409:1727:32
8:52
#21664
15K
9.32 mi12:44:201:24:349:0426:54
8:39
#20905
20K
12.43 mi13:11:401:51:549:0027:20
8:48
#20385
Half
13.11 mi13:17:201:57:348:585:40
8:18
#20218
25K
15.53 mi13:38:032:18:178:5420:43
8:33
#19629
30K
18.64 mi14:04:492:45:038:5126:46
8:37
#18850
20M
20.00 mi14:16:462:57:008:5111:57
8:48
#18605
21M
21.00 mi14:25:393:05:538:518:53
8:53
#18285
35K
21.75 mi14:31:323:11:468:495:53
7:52
#18046
23M
23.00 mi14:42:063:22:208:4810:34
8:26
#17754
24M
24.00 mi14:50:283:30:428:478:22
8:22
#17574
40K
24.85 mi14:57:533:38:078:477:25
8:40
#17452
25.2M
25.20 mi15:00:543:41:088:473:01
8:45
#17352
Finish
26.22 mi15:08:383:48:528:447:44
7:35
#17076
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi22645134151341518758(Top 70%)11779(Top 78%)11779(Top 223%)
10K6.21 mi3.10 mi21664+98112972+44312972+44320220(Top 76%)12364(Top 81%)12364(Top 234%)
15K9.32 mi3.11 mi20905+75912650+32212650+32218758(Top 70%)11779(Top 78%)11779(Top 223%)
20K12.43 mi3.11 mi20385+52012428+22212428+22218649(Top 70%)11743(Top 77%)11743(Top 222%)
Half13.11 mi0.68 mi20218+16712360+6812360+6816483(Top 62%)10875(Top 72%)10875(Top 206%)
25K15.53 mi2.42 mi19629+58912107+25312107+25316455(Top 62%)10738(Top 71%)10738(Top 203%)
30K18.64 mi3.11 mi18850+77911775+33211775+33215004(Top 56%)10059(Top 66%)10059(Top 190%)
20M20.00 mi1.36 mi18605+24511649+12611649+12615393(Top 58%)10170(Top 67%)10170(Top 192%)
21M21.00 mi1.00 mi18285+32011496+15311496+15312755(Top 48%)8930(Top 59%)8930(Top 169%)
35K21.75 mi0.75 mi18046+23911401+9511401+9511129(Top 42%)8198(Top 54%)8198(Top 155%)
23M23.00 mi1.25 mi17754+29211259+14211259+14212853(Top 48%)8859(Top 58%)8859(Top 168%)
24M24.00 mi1.00 mi17574+18011173+8611173+8613638(Top 51%)9162(Top 60%)9162(Top 173%)
40K24.85 mi0.85 mi17452+12211116+5711116+5714360(Top 54%)9402(Top 62%)9402(Top 178%)
25.2M25.20 mi0.35 mi17352+10011065+5111065+5111008(Top 41%)7819(Top 52%)7819(Top 148%)
Finish26.22 mi1.02 mi17076+27610938+12710938+1279208(Top 35%)6878(Top 45%)6878(Top 130%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 70%
×21stories
+97ft-345ft

Overall

18758

Males

11779

M18-39

11779

5K→10K

3.1 - 6.2 mi

Top 76%
×5stories
+79ft-138ft

Overall

20220

Males

12364

M18-39

12364

10K→15K

6.2 - 9.3 mi

Top 70%
×3stories
+67ft-78ft

Overall

18758

Males

11779

M18-39

11779

15K→20K

9.3 - 12.4 mi

Top 70%
×5stories
+106ft-86ft

Overall

18649

Males

11743

M18-39

11743

20K→Half

12.4 - 13.1 mi

Top 62%
×2stories
+19ft-37ft

Overall

16483

Males

10875

M18-39

10875

Half→25K

13.1 - 15.5 mi

Top 62%
×4stories
+66ft-88ft

Overall

16455

Males

10738

M18-39

10738

25K→30K

15.5 - 18.6 mi

Top 56%
×9stories
+181ft-148ft

Overall

15004

Males

10059

M18-39

10059

30K→20M

18.6 - 20.0 mi

Top 58%
×5stories
+64ft-50ft

Overall

15393

Males

10170

M18-39

10170

20M→21M

20.0 - 21.0 mi

Top 48%
×8stories
+106ft-24ft

Overall

12755

Males

8930

M18-39

8930

21M→35K

21.0 - 21.8 mi

Top 42%
×7stories
+17ft-86ft

Overall

11129

Males

8198

M18-39

8198

35K→23M

21.8 - 23.0 mi

Top 48%
×5stories
+23ft-63ft

Overall

12853

Males

8859

M18-39

8859

23M→24M

23.0 - 24.0 mi

Top 51%
×6stories
+12ft-82ft

Overall

13638

Males

9162

M18-39

9162

24M→40K

24.0 - 24.9 mi

Top 54%
×1story
+6ft-20ft

Overall

14360

Males

9402

M18-39

9402

40K→25.2M

24.9 - 25.2 mi

Top 41%
×1story
+13ft-16ft

Overall

11008

Males

7819

M18-39

7819

25.2M→Finish

25.2 - 26.2 mi

Top 35%
×2stories
+22ft-21ft

Overall

9208

Males

6878

M18-39

6878

Passing Analysis

Category:
Athletes Passed
5636
Passed By
67
Net Change
+5569
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#22645
5K → 10K100221+981#22645#21664
10K → 15K7634+759#21664#20905
15K → 20K53111+520#20905#20385
20K → Half1670+167#20385#20218
Half → 25K5901+589#20218#19629
25K → 30K7823+779#19629#18850
30K → 20M2505+245#18850#18605
20M → 21M3222+320#18605#18285
21M → 35K2401+239#18285#18046
35K → 23M2942+292#18046#17754
23M → 24M1822+180#17754#17574
24M → 40K13210+122#17574#17452
40K → 25.2M1022+100#17452#17352
25.2M → Finish2793+276#17352#17076
TOTALS563667+5569
📊

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