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BOSTON MARATHON 2024

Spencer Tsai

Bib: 2321•M

VA

0:00
0:00
/ mi
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Overall
#0 / 25550
Top 1%
Gender (Male)
#0 / 14578
Top 2%
Division (M18-39)
#0 / 4849
Top 6%
Race Day Weather
55°/45°F
scattered clouds

⏱️ 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
6:01/mi
18:42
↑ 97↓ 3451.5%
10K· 6.21 mi
5:58/mi
37:13
↑ 79↓ 1380.4%
15K· 9.32 mi
5:58/mi
55:44
↑ 67↓ 78
20K· 12.43 mi
5:58/mi
1:14:17
↑ 106↓ 860.1%
Half· 13.11 mi
5:50/mi
1:18:16
↑ 19↓ 370.5%
25K· 15.53 mi
5:58/mi
1:32:44
↑ 66↓ 880.2%
30K· 18.64 mi
6:08/mi
1:51:48
↑ 181↓ 1480.2%
20M
6:13/mi
2:00:15
↑ 64↓ 500.2%
21M
6:30/mi
2:06:45
↑ 106↓ 241.6%
35K· 21.75 mi
6:06/mi
2:11:19
↑ 17↓ 861.7%
23M
6:07/mi
2:18:58
↑ 23↓ 630.6%
24M
6:01/mi
2:24:59
↓ 821.3%
40K· 24.85 mi
6:06/mi
2:30:12
↓ 200.3%
25.2M
6:31/mi
2:32:27
↑ 13↓ 160.2%
Finish· 26.22 mi
5:49/mi
2:38:23
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:18:16
Pace5:58 /mi
2nd Half
Distance13.11 mi
Time1:20:07
Pace6:07 /mi
📊Positive Split: 2.4% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:19:5918:426:0118:42
6:01
-
10K
6.21 mi10:38:3037:135:5918:31
5:58
-0:03
15K
9.32 mi10:57:0155:445:5918:31
5:58
0:00
20K
12.43 mi11:15:341:14:175:5918:33
5:58
0:00
Half
13.11 mi11:19:331:18:165:583:59
5:50
-0:08
25K
15.53 mi11:34:011:32:445:5814:28
5:58
+0:08
30K
18.64 mi11:53:051:51:486:0019:04
6:08
+0:10
20M
20.00 mi12:01:322:00:156:018:27
6:13
+0:05
21M
21.00 mi12:08:022:06:456:026:30
6:30
+0:17
35K
21.75 mi12:12:362:11:196:024:34
6:06
-0:24
23M
23.00 mi12:20:152:18:586:037:39
6:07
+0:01
24M
24.00 mi12:26:162:24:596:026:01
6:01
-0:06
40K
24.85 mi12:31:292:30:126:035:13
6:06
+0:05
25.2M
25.20 mi12:33:442:32:276:032:15
6:31
+0:25
Finish
26.22 mi12:39:402:38:236:035:56
5:49
-0:42

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

5:49 /mi

Average Pace

6:03 /mi

Slowest Pace

6:31 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:29:38

94% of race

Time at Steady Pace

8:45

6% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 6:02 /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 mi10:19:5918:426:0118:42
6:01
#970
10K
6.21 mi10:38:3037:135:5918:31
5:58
#847
15K
9.32 mi10:57:0155:445:5918:31
5:58
#782
20K
12.43 mi11:15:341:14:175:5918:33
5:58
#707
Half
13.11 mi11:19:331:18:165:583:59
5:50
#698
25K
15.53 mi11:34:011:32:445:5814:28
5:58
#614
30K
18.64 mi11:53:051:51:486:0019:04
6:08
#536
20M
20.00 mi12:01:322:00:156:018:27
6:13
#501
21M
21.00 mi12:08:022:06:456:026:30
6:30
#477
35K
21.75 mi12:12:362:11:196:024:34
6:06
#468
23M
23.00 mi12:20:152:18:586:037:39
6:07
#435
24M
24.00 mi12:26:162:24:596:026:01
6:01
#413
40K
24.85 mi12:31:292:30:126:035:13
6:06
#392
25.2M
25.20 mi12:33:442:32:276:032:15
6:31
#377
Finish
26.22 mi12:39:402:38:236:035:56
5:49
#347
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi970933933684(Top 3%)661(Top 5%)661(Top 14%)
10K6.21 mi3.10 mi847+123819+114819+114763(Top 3%)736(Top 5%)736(Top 15%)
15K9.32 mi3.11 mi782+65755+64755+64684(Top 3%)661(Top 5%)661(Top 14%)
20K12.43 mi3.11 mi707+75681+74681+74520(Top 2%)497(Top 3%)497(Top 10%)
Half13.11 mi0.68 mi698+9673+8673+8437(Top 2%)415(Top 3%)415(Top 9%)
25K15.53 mi2.42 mi614+84590+83590+83410(Top 2%)387(Top 3%)387(Top 8%)
30K18.64 mi3.11 mi536+78512+78512+78390(Top 2%)362(Top 2%)362(Top 7%)
20M20.00 mi1.36 mi501+35477+35477+35407(Top 2%)378(Top 3%)378(Top 8%)
21M21.00 mi1.00 mi477+24453+24453+24334(Top 1%)312(Top 2%)312(Top 6%)
35K21.75 mi0.75 mi468+9444+9444+9476(Top 2%)444(Top 3%)444(Top 9%)
23M23.00 mi1.25 mi435+33409+35409+35249(Top 1.0%)227(Top 2%)227(Top 5%)
24M24.00 mi1.00 mi413+22387+22387+22279(Top 1%)254(Top 2%)254(Top 5%)
40K24.85 mi0.85 mi392+21366+21366+21256(Top 1%)232(Top 2%)232(Top 5%)
25.2M25.20 mi0.35 mi377+15351+15351+15181(Top 0.7%)166(Top 1%)166(Top 3%)
Finish26.22 mi1.02 mi347+30322+29322+29251(Top 1.0%)233(Top 2%)233(Top 5%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 3%
×21story building
+97ft-345ft

Overall

684

Males

661

M18-39

661

5K→10K

3.1 - 6.2 mi

Top 3%
×5story building
+79ft-138ft

Overall

763

Males

736

M18-39

736

10K→15K

6.2 - 9.3 mi

Top 3%
×3story building
+67ft-78ft

Overall

684

Males

661

M18-39

661

15K→20K

9.3 - 12.4 mi

Top 2%
×5story building
+106ft-86ft

Overall

520

Males

497

M18-39

497

20K→Half

12.4 - 13.1 mi

Top 2%
×2story building
+19ft-37ft

Overall

437

Males

415

M18-39

415

Half→25K

13.1 - 15.5 mi

Top 2%
×4story building
+66ft-88ft

Overall

410

Males

387

M18-39

387

25K→30K

15.5 - 18.6 mi

Top 2%
×9story building
+181ft-148ft

Overall

390

Males

362

M18-39

362

30K→20M

18.6 - 20.0 mi

Top 2%
×5story building
+64ft-50ft

Overall

407

Males

378

M18-39

378

20M→21M

20.0 - 21.0 mi

Top 1%
×8story building
+106ft-24ft

Overall

334

Males

312

M18-39

312

21M→35K

21.0 - 21.8 mi

Top 2%
×7story building
+17ft-86ft

Overall

476

Males

444

M18-39

444

35K→23M

21.8 - 23.0 mi

Top 1.0%
×5story building
+23ft-63ft

Overall

249

Males

227

M18-39

227

23M→24M

23.0 - 24.0 mi

Top 1%
×6story building
+12ft-82ft

Overall

279

Males

254

M18-39

254

24M→40K

24.0 - 24.9 mi

Top 1%
×1story
+6ft-20ft

Overall

256

Males

232

M18-39

232

40K→25.2M

24.9 - 25.2 mi

Top 0.7%
×1story
+13ft-16ft

Overall

181

Males

166

M18-39

166

25.2M→Finish

25.2 - 26.2 mi

Top 1.0%
×2story building
+22ft-21ft

Overall

251

Males

233

M18-39

233

Passing Analysis

Category:
Athletes Passed
671
Passed By
48
Net Change
+623
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#970
5K → 10K13411+123#970#847
10K → 15K738+65#847#782
15K → 20K794+75#782#707
20K → Half101+9#707#698
Half → 25K851+84#698#614
25K → 30K824+78#614#536
30K → 20M394+35#536#501
20M → 21M262+24#501#477
21M → 35K145+9#477#468
35K → 23M363+33#468#435
23M → 24M231+22#435#413
24M → 40K232+21#413#392
40K → 25.2M150+15#392#377
25.2M → Finish322+30#377#347
TOTALS67148+623
📊

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