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BOSTON MARATHON 2023

Leo Chang

Bib: 2235•M

OR

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Top 10%
Gender (Male)
#0 / 15176
Top 17%
Masters (Masters Men)
#0 / 9891
Top 6%
Division (M40-44)
#0 / 2241
Top 17%
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
20:45
Rank: #3460
Start → 5K
20:45 | 6:41/mi
10K· 6.21 mi
41:13
Rank: #3401 (+59)
5K → 10K
20:28 | 6:35/mi
15K· 9.32 mi
1:01:33
Rank: #3223 (+178)
10K → 15K
20:20 | 6:33/mi
20K· 12.43 mi
1:22:11
Rank: #3162 (+61)
15K → 20K
20:38 | 6:38/mi
Half· 13.11 mi
1:26:40
Rank: #3160 (+2)
20K → Half
4:29 | 6:34/mi
25K· 15.53 mi
1:42:40
Rank: #3058 (+102)
Half → 25K
16:00 | 6:36/mi
30K· 18.64 mi
2:04:12
Rank: #3138 (-80)
25K → 30K
21:32 | 6:56/mi
20M
2:13:57
Rank: #3272 (-134)
30K → 20M
9:45 | 7:10/mi
21M
2:21:27
Rank: #3328 (-56)
20M → 21M
7:30 | 7:30/mi
35K· 21.75 mi
2:26:22
Rank: #3291 (+37)
21M → 35K
4:55 | 6:34/mi
23M
2:34:31
Rank: #3107 (+184)
35K → 23M
8:09 | 6:31/mi
24M
2:40:42
Rank: #2943 (+164)
23M → 24M
6:11 | 6:11/mi
40K· 24.85 mi
2:46:14
Rank: #2835 (+108)
24M → 40K
5:32 | 6:28/mi
25.2M
2:48:44
Rank: #2820 (+15)
40K → 25.2M
2:30 | 7:15/mi
Finish· 26.22 mi
2:55:08
Rank: #2729 (+91)
25.2M → Finish
6:24 | 6:17/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:26:40
Pace6:37 /mi
2nd Half
Distance13.11 mi
Time1:28:28
Pace6:45 /mi
📊Positive Split: 2.1% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:21:2520:456:4120:45
6:41
-
10K
6.21 mi10:41:5341:136:3820:28
6:35
-0:06
15K
9.32 mi11:02:131:01:336:3620:20
6:33
-0:02
20K
12.43 mi11:22:511:22:116:3720:38
6:38
+0:05
Half
13.11 mi11:27:201:26:406:374:29
6:34
-0:04
25K
15.53 mi11:43:201:42:406:3716:00
6:36
+0:02
30K
18.64 mi12:04:522:04:126:4021:32
6:56
+0:20
20M
20.00 mi12:14:372:13:576:429:45
7:10
+0:14
21M
21.00 mi12:22:072:21:276:447:30
7:30
+0:20
35K
21.75 mi12:27:022:26:226:444:55
6:34
-0:56
23M
23.00 mi12:35:112:34:316:438:09
6:31
-0:03
24M
24.00 mi12:41:222:40:426:426:11
6:11
-0:20
40K
24.85 mi12:46:542:46:146:415:32
6:28
+0:17
25.2M
25.20 mi12:49:242:48:446:422:30
7:15
+0:47
Finish
26.22 mi12:55:482:55:086:416:24
6:17
-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

6:11 /mi

Average Pace

6:41 /mi

Slowest Pace

7:30 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

12:35

7% of race

Time at Steady Pace

2:01:16

69% of race

Time at Slower Pace

41:17

24% of race

Average Pace: 6:41 /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 mi10:21:2520:456:4120:45
6:41
#3460
10K
6.21 mi10:41:5341:136:3820:28
6:35
#3401
15K
9.32 mi11:02:131:01:336:3620:20
6:33
#3223
20K
12.43 mi11:22:511:22:116:3720:38
6:38
#3162
Half
13.11 mi11:27:201:26:406:374:29
6:34
#3160
25K
15.53 mi11:43:201:42:406:3716:00
6:36
#3058
30K
18.64 mi12:04:522:04:126:4021:32
6:56
#3138
20M
20.00 mi12:14:372:13:576:429:45
7:10
#3272
21M
21.00 mi12:22:072:21:276:447:30
7:30
#3328
35K
21.75 mi12:27:022:26:226:444:55
6:34
#3291
23M
23.00 mi12:35:112:34:316:438:09
6:31
#3107
24M
24.00 mi12:41:222:40:426:426:11
6:11
#2943
40K
24.85 mi12:46:542:46:146:415:32
6:28
#2835
25.2M
25.20 mi12:49:242:48:446:422:30
7:15
#2820
Finish
26.22 mi12:55:482:55:086:416:24
6:17
#2729
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM40-44Seg. OverallSeg. MalesSeg. M40-44
5K3.11 mi3.11 mi3460326132612897(Top 11%)2769(Top 18%)2769(Top 124%)
10K6.21 mi3.10 mi3401+593216+453216+453397(Top 13%)3226(Top 21%)3226(Top 144%)
15K9.32 mi3.11 mi3223+1783067+1493067+1492897(Top 11%)2769(Top 18%)2769(Top 124%)
20K12.43 mi3.11 mi3162+613010+573010+573101(Top 12%)2948(Top 19%)2948(Top 132%)
Half13.11 mi0.68 mi3160+2301030103195(Top 12%)3045(Top 20%)3045(Top 136%)
25K15.53 mi2.42 mi3058+1022916+942916+942703(Top 10%)2587(Top 17%)2587(Top 115%)
30K18.64 mi3.11 mi3138-802989-732989-733857(Top 14%)3612(Top 24%)3612(Top 161%)
20M20.00 mi1.36 mi3272-1343103-1143103-1144952(Top 19%)4498(Top 30%)4498(Top 201%)
21M21.00 mi1.00 mi3328-563153-503153-504538(Top 17%)4125(Top 27%)4125(Top 184%)
35K21.75 mi0.75 mi3291+373117+363117+362819(Top 11%)2646(Top 17%)2646(Top 118%)
23M23.00 mi1.25 mi3107+1842949+1682949+1681471(Top 6%)1398(Top 9%)1398(Top 62%)
24M24.00 mi1.00 mi2943+1642798+1512798+151991(Top 4%)940(Top 6%)940(Top 42%)
40K24.85 mi0.85 mi2835+1082695+1032695+1031456(Top 5%)1375(Top 9%)1375(Top 61%)
25.2M25.20 mi0.35 mi2820+152680+152680+152691(Top 10%)2477(Top 16%)2477(Top 111%)
Finish26.22 mi1.02 mi2729+912596+842596+841553(Top 6%)1468(Top 10%)1468(Top 66%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 11%
×21stories
+97ft-345ft

Overall

2897

Males

2769

M40-44

2769

5K→10K

3.1 - 6.2 mi

Top 13%
×5stories
+79ft-138ft

Overall

3397

Males

3226

M40-44

3226

10K→15K

6.2 - 9.3 mi

Top 11%
×3stories
+67ft-78ft

Overall

2897

Males

2769

M40-44

2769

15K→20K

9.3 - 12.4 mi

Top 12%
×5stories
+106ft-86ft

Overall

3101

Males

2948

M40-44

2948

20K→Half

12.4 - 13.1 mi

Top 12%
×2stories
+19ft-37ft

Overall

3195

Males

3045

M40-44

3045

Half→25K

13.1 - 15.5 mi

Top 10%
×4stories
+66ft-88ft

Overall

2703

Males

2587

M40-44

2587

25K→30K

15.5 - 18.6 mi

Top 14%
×9stories
+181ft-148ft

Overall

3857

Males

3612

M40-44

3612

30K→20M

18.6 - 20.0 mi

Top 19%
×5stories
+64ft-50ft

Overall

4952

Males

4498

M40-44

4498

20M→21M

20.0 - 21.0 mi

Top 17%
×8stories
+106ft-24ft

Overall

4538

Males

4125

M40-44

4125

21M→35K

21.0 - 21.8 mi

Top 11%
×7stories
+17ft-86ft

Overall

2819

Males

2646

M40-44

2646

35K→23M

21.8 - 23.0 mi

Top 6%
×5stories
+23ft-63ft

Overall

1471

Males

1398

M40-44

1398

23M→24M

23.0 - 24.0 mi

Top 4%
×6stories
+12ft-82ft

Overall

991

Males

940

M40-44

940

24M→40K

24.0 - 24.9 mi

Top 5%
×1story
+6ft-20ft

Overall

1456

Males

1375

M40-44

1375

40K→25.2M

24.9 - 25.2 mi

Top 10%
×1story
+13ft-16ft

Overall

2691

Males

2477

M40-44

2477

25.2M→Finish

25.2 - 26.2 mi

Top 6%
×2stories
+22ft-21ft

Overall

1553

Males

1468

M40-44

1468

Passing Analysis

Category:
Athletes Passed
1441
Passed By
710
Net Change
+731
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#3460
5K → 10K219160+59#3460#3401
10K → 15K20931+178#3401#3223
15K → 20K11655+61#3223#3162
20K → Half2018+2#3162#3160
Half → 25K11715+102#3160#3058
25K → 30K67147-80#3058#3138
30K → 20M27161-134#3138#3272
20M → 21M3389-56#3272#3328
21M → 35K458+37#3328#3291
35K → 23M1873+184#3291#3107
23M → 24M1651+164#3107#2943
24M → 40K1102+108#2943#2835
40K → 25.2M3015+15#2835#2820
25.2M → Finish965+91#2820#2729
TOTALS1441710+731
📊

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