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BOSTON MARATHON 2023

David Lam

Bib: 4349•M

CA

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 17%
Gender (Male)
#0 / 15176
Top 28%
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
20:32
Rank: #2929
Start → 5K
6:37/mi
20:32 split
10K· 6.21 mi
40:42
Rank: #2803 (+126)
5K → 10K
6:29/mi
20:10 split
15K· 9.32 mi
1:01:06
Rank: #2862 (-59)
10K → 15K
6:34/mi
20:24 split
20K· 12.43 mi
1:21:46
Rank: #2932 (-70)
15K → 20K
6:39/mi
20:40 split
Half· 13.11 mi
1:26:19
Rank: #2988 (-56)
20K → Half
6:40/mi
4:33 split
25K· 15.53 mi
1:42:49
Rank: #3129 (-141)
Half → 25K
6:48/mi
16:30 split
30K· 18.64 mi
2:05:02
Rank: #3501 (-372)
25K → 30K
7:09/mi
22:13 split
20M
2:14:46
Rank: #3604 (-103)
30K → 20M
7:10/mi
9:44 split
21M
2:22:26
Rank: #3723 (-119)
20M → 21M
7:40/mi
7:40 split
35K· 21.75 mi
2:27:53
Rank: #3873 (-150)
21M → 35K
7:16/mi
5:27 split
23M
2:36:59
Rank: #3978 (-105)
35K → 23M
7:16/mi
9:06 split
24M
2:44:25
Rank: #4195 (-217)
23M → 24M
7:26/mi
7:26 split
40K· 24.85 mi
2:51:02
Rank: #4359 (-164)
24M → 40K
7:44/mi
6:37 split
25.2M
2:53:50
Rank: #4400 (-41)
40K → 25.2M
8:07/mi
2:48 split
Finish· 26.22 mi
3:01:32
Rank: #4523 (-123)
25.2M → Finish
7:33/mi
7:42 split

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:26:19
Pace6:35 /mi
2nd Half
Distance13.11 mi
Time1:35:13
Pace7:16 /mi
📊Positive Split: 10.3% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:24:1420:326:3720:32
6:37
-
10K
6.21 mi10:44:2440:426:3320:10
6:29
-0:08
15K
9.32 mi11:04:481:01:066:3320:24
6:34
+0:05
20K
12.43 mi11:25:281:21:466:3520:40
6:39
+0:05
Half
13.11 mi11:30:011:26:196:354:33
6:40
+0:01
25K
15.53 mi11:46:311:42:496:3716:30
6:48
+0:08
30K
18.64 mi12:08:442:05:026:4222:13
7:09
+0:21
20M
20.00 mi12:18:282:14:466:449:44
7:10
+0:01
21M
21.00 mi12:26:082:22:266:477:40
7:40
+0:30
35K
21.75 mi12:31:352:27:536:485:27
7:16
-0:24
23M
23.00 mi12:40:412:36:596:509:06
7:16
0:00
24M
24.00 mi12:48:072:44:256:517:26
7:26
+0:10
40K
24.85 mi12:54:442:51:026:536:37
7:44
+0:18
25.2M
25.20 mi12:57:322:53:506:542:48
8:07
+0:23
Finish
26.22 mi13:05:143:01:326:567:42
7:33
-0:34

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

6:29 /mi

Average Pace

6:56 /mi

Slowest Pace

8:07 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:42:49

57% of race

Time at Steady Pace

46:30

26% of race

Time at Slower Pace

32:13

18% of race

Average Pace: 6:55 /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 mi10:24:1420:326:3720:32
6:37
#2929
10K
6.21 mi10:44:2440:426:3320:10
6:29
#2803
15K
9.32 mi11:04:481:01:066:3320:24
6:34
#2862
20K
12.43 mi11:25:281:21:466:3520:40
6:39
#2932
Half
13.11 mi11:30:011:26:196:354:33
6:40
#2988
25K
15.53 mi11:46:311:42:496:3716:30
6:48
#3129
30K
18.64 mi12:08:442:05:026:4222:13
7:09
#3501
20M
20.00 mi12:18:282:14:466:449:44
7:10
#3604
21M
21.00 mi12:26:082:22:266:477:40
7:40
#3723
35K
21.75 mi12:31:352:27:536:485:27
7:16
#3873
23M
23.00 mi12:40:412:36:596:509:06
7:16
#3978
24M
24.00 mi12:48:072:44:256:517:26
7:26
#4195
40K
24.85 mi12:54:442:51:026:536:37
7:44
#4359
25.2M
25.20 mi12:57:322:53:506:542:48
8:07
#4400
Finish
26.22 mi13:05:143:01:326:567:42
7:33
#4523
Faster pace
Steady pace
Slower pace
Est.Checkpoint not recorded (estimated)
~Segment time uses estimated prior

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi2929278327833040(Top 11%)2899(Top 19%)2899(Top 55%)
10K6.21 mi3.10 mi2803+1262673+1102673+1102739(Top 10%)2620(Top 17%)2620(Top 50%)
15K9.32 mi3.11 mi2862-592733-602733-603040(Top 11%)2899(Top 19%)2899(Top 55%)
20K12.43 mi3.11 mi2932-702802-692802-693204(Top 12%)3045(Top 20%)3045(Top 58%)
Half13.11 mi0.68 mi2988-562854-522854-524072(Top 15%)3824(Top 25%)3824(Top 72%)
25K15.53 mi2.42 mi3129-1412981-1272981-1274208(Top 16%)3939(Top 26%)3939(Top 75%)
30K18.64 mi3.11 mi3501-3723314-3333314-3335214(Top 20%)4766(Top 31%)4766(Top 90%)
20M20.00 mi1.36 mi3604-1033409-953409-954908(Top 18%)4463(Top 29%)4463(Top 84%)
21M21.00 mi1.00 mi3723-1193514-1053514-1055420(Top 20%)4773(Top 31%)4773(Top 90%)
35K21.75 mi0.75 mi3873-1503642-1283642-1286970(Top 26%)5855(Top 39%)5855(Top 111%)
23M23.00 mi1.25 mi3978-1053732-903732-905181(Top 19%)4589(Top 30%)4589(Top 87%)
24M24.00 mi1.00 mi4195-2173926-1943926-1947214(Top 27%)5827(Top 38%)5827(Top 110%)
40K24.85 mi0.85 mi4359-1644071-1454071-1458179(Top 31%)6343(Top 42%)6343(Top 120%)
25.2M25.20 mi0.35 mi4400-414105-344105-347091(Top 27%)5605(Top 37%)5605(Top 106%)
Finish26.22 mi1.02 mi4523-1234203-984203-988908(Top 33%)6686(Top 44%)6686(Top 127%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 11%
×21story building
+97ft-345ft

Overall

3040

Males

2899

M18-39

2899

5K→10K

3.1 - 6.2 mi

Top 10%
×5story building
+79ft-138ft

Overall

2739

Males

2620

M18-39

2620

10K→15K

6.2 - 9.3 mi

Top 11%
×3story building
+67ft-78ft

Overall

3040

Males

2899

M18-39

2899

15K→20K

9.3 - 12.4 mi

Top 12%
×5story building
+106ft-86ft

Overall

3204

Males

3045

M18-39

3045

20K→Half

12.4 - 13.1 mi

Top 15%
×2story building
+19ft-37ft

Overall

4072

Males

3824

M18-39

3824

Half→25K

13.1 - 15.5 mi

Top 16%
×4story building
+66ft-88ft

Overall

4208

Males

3939

M18-39

3939

25K→30K

15.5 - 18.6 mi

Top 20%
×9story building
+181ft-148ft

Overall

5214

Males

4766

M18-39

4766

30K→20M

18.6 - 20.0 mi

Top 18%
×5story building
+64ft-50ft

Overall

4908

Males

4463

M18-39

4463

20M→21M

20.0 - 21.0 mi

Top 20%
×8story building
+106ft-24ft

Overall

5420

Males

4773

M18-39

4773

21M→35K

21.0 - 21.8 mi

Top 26%
×7story building
+17ft-86ft

Overall

6970

Males

5855

M18-39

5855

35K→23M

21.8 - 23.0 mi

Top 19%
×5story building
+23ft-63ft

Overall

5181

Males

4589

M18-39

4589

23M→24M

23.0 - 24.0 mi

Top 27%
×6story building
+12ft-82ft

Overall

7214

Males

5827

M18-39

5827

24M→40K

24.0 - 24.9 mi

Top 31%
×1story
+6ft-20ft

Overall

8179

Males

6343

M18-39

6343

40K→25.2M

24.9 - 25.2 mi

Top 27%
×1story
+13ft-16ft

Overall

7091

Males

5605

M18-39

5605

25.2M→Finish

25.2 - 26.2 mi

Top 33%
×2story building
+22ft-21ft

Overall

8908

Males

6686

M18-39

6686

Passing Analysis

Category:
Athletes Passed
562
Passed By
2156
Net Change
-1594
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#2929
5K → 10K227101+126#2929#2803
10K → 15K68127-59#2803#2862
15K → 20K51121-70#2862#2932
20K → Half359-56#2932#2988
Half → 25K26167-141#2988#3129
25K → 30K20392-372#3129#3501
30K → 20M34137-103#3501#3604
20M → 21M30149-119#3604#3723
21M → 35K5155-150#3723#3873
35K → 23M32137-105#3873#3978
23M → 24M16233-217#3978#4195
24M → 40K17181-164#4195#4359
40K → 25.2M1758-41#4359#4400
25.2M → Finish16139-123#4400#4523
TOTALS5622156-1594
📊

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