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BOSTON MARATHON 2023

Samalya Schaefer

Bib: 1556•M

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 1%
Gender (Male)
#0 / 15176
Top 2%
Division (M18-39)
#0 / 5285
Top 5%
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ 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
5:35/mi
17:20
↑ 97↓ 3451.5%
10K· 6.21 mi
5:35/mi
34:40
↑ 79↓ 1380.4%
15K· 9.32 mi
5:40/mi
52:15
↑ 67↓ 78
20K· 12.43 mi
5:43/mi
1:10:01
↑ 106↓ 860.1%
Half· 13.11 mi
5:36/mi
1:13:50
↑ 19↓ 370.5%
25K· 15.53 mi
5:49/mi
1:27:56
↑ 66↓ 880.2%
30K· 18.64 mi
5:56/mi
1:46:23
↑ 181↓ 1480.2%
20M
6:08/mi
1:54:43
↑ 64↓ 500.2%
21M
6:26/mi
2:01:09
↑ 106↓ 241.6%
35K· 21.75 mi
6:08/mi
2:05:44
↑ 17↓ 861.7%
23M
6:31/mi
2:13:53
↑ 23↓ 630.6%
24M
6:25/mi
2:20:18
↓ 821.3%
40K· 24.85 mi
6:34/mi
2:25:55
↓ 200.3%
25.2M
7:15/mi
2:28:25
↑ 13↓ 160.2%
Finish· 26.22 mi
6:38/mi
2:35:11
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:13:50
Pace5:38 /mi
2nd Half
Distance13.11 mi
Time1:21:21
Pace6:12 /mi
📊Positive Split: 10.2% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:17:2817:205:3517:20
5:35
-
10K
6.21 mi10:34:4834:405:3517:20
5:35
0:00
15K
9.32 mi10:52:2352:155:3617:35
5:40
+0:05
20K
12.43 mi11:10:091:10:015:3817:46
5:43
+0:03
Half
13.11 mi11:13:581:13:505:383:49
5:36
-0:07
25K
15.53 mi11:28:041:27:565:4014:06
5:49
+0:13
30K
18.64 mi11:46:311:46:235:4218:27
5:56
+0:07
20M
20.00 mi11:54:511:54:435:448:20
6:08
+0:12
21M
21.00 mi12:01:172:01:095:466:26
6:26
+0:18
35K
21.75 mi12:05:522:05:445:474:35
6:08
-0:18
23M
23.00 mi12:14:012:13:535:498:09
6:31
+0:23
24M
24.00 mi12:20:262:20:185:516:25
6:25
-0:06
40K
24.85 mi12:26:032:25:555:525:37
6:34
+0:09
25.2M
25.20 mi12:28:332:28:255:532:30
7:15
+0:41
Finish
26.22 mi12:35:192:35:115:556:46
6:38
-0:37

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

5:35 /mi

Average Pace

5:55 /mi

Slowest Pace

7:15 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:27:56

57% of race

Time at Steady Pace

31:22

20% of race

Time at Slower Pace

35:53

23% of race

Average Pace: 5:55 /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 mi10:17:2817:205:3517:20
5:35
#170
10K
6.21 mi10:34:4834:405:3517:20
5:35
#159
15K
9.32 mi10:52:2352:155:3617:35
5:40
#183
20K
12.43 mi11:10:091:10:015:3817:46
5:43
#191
Half
13.11 mi11:13:581:13:505:383:49
5:36
#191
25K
15.53 mi11:28:041:27:565:4014:06
5:49
#196
30K
18.64 mi11:46:311:46:235:4218:27
5:56
#197
20M
20.00 mi11:54:511:54:435:448:20
6:08
#210
21M
21.00 mi12:01:172:01:095:466:26
6:26
#224
35K
21.75 mi12:05:522:05:445:474:35
6:08
#239
23M
23.00 mi12:14:012:13:535:498:09
6:31
#265
24M
24.00 mi12:20:262:20:185:516:25
6:25
#278
40K
24.85 mi12:26:032:25:555:525:37
6:34
#294
25.2M
25.20 mi12:28:332:28:255:532:30
7:15
#308
Finish
26.22 mi12:35:192:35:115:556:46
6:38
#333
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi170170170200(Top 0.8%)172(Top 1%)172(Top 3%)
10K6.21 mi3.10 mi159+11159+11159+11192(Top 0.7%)165(Top 1%)165(Top 3%)
15K9.32 mi3.11 mi183-24158+1158+1200(Top 0.8%)172(Top 1%)172(Top 3%)
20K12.43 mi3.11 mi191-8166-8166-8213(Top 0.8%)188(Top 1%)188(Top 4%)
Half13.11 mi0.68 mi191167-1167-1191(Top 0.7%)169(Top 1%)169(Top 3%)
25K15.53 mi2.42 mi196-5171-4171-4298(Top 1%)270(Top 2%)270(Top 5%)
30K18.64 mi3.11 mi197-1173-2173-2305(Top 1%)280(Top 2%)280(Top 5%)
20M20.00 mi1.36 mi210-13186-13186-13524(Top 2%)490(Top 3%)490(Top 9%)
21M21.00 mi1.00 mi224-14199-13199-13530(Top 2%)496(Top 3%)496(Top 9%)
35K21.75 mi0.75 mi239-15213-14213-14981(Top 4%)931(Top 6%)931(Top 18%)
23M23.00 mi1.25 mi265-26239-26239-261429(Top 5%)1356(Top 9%)1356(Top 26%)
24M24.00 mi1.00 mi278-13250-11250-111712(Top 6%)1613(Top 11%)1613(Top 31%)
40K24.85 mi0.85 mi294-16264-14264-141765(Top 7%)1660(Top 11%)1660(Top 31%)
25.2M25.20 mi0.35 mi308-14278-14278-142628(Top 10%)2414(Top 16%)2414(Top 46%)
Finish26.22 mi1.02 mi333-25302-24302-243157(Top 12%)2834(Top 19%)2834(Top 54%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 0.8%
×21story building
+97ft-345ft

Overall

200

Males

172

M18-39

172

5K→10K

3.1 - 6.2 mi

Top 0.7%
×5story building
+79ft-138ft

Overall

192

Males

165

M18-39

165

10K→15K

6.2 - 9.3 mi

Top 0.8%
×3story building
+67ft-78ft

Overall

200

Males

172

M18-39

172

15K→20K

9.3 - 12.4 mi

Top 0.8%
×5story building
+106ft-86ft

Overall

213

Males

188

M18-39

188

20K→Half

12.4 - 13.1 mi

Top 0.7%
×2story building
+19ft-37ft

Overall

191

Males

169

M18-39

169

Half→25K

13.1 - 15.5 mi

Top 1%
×4story building
+66ft-88ft

Overall

298

Males

270

M18-39

270

25K→30K

15.5 - 18.6 mi

Top 1%
×9story building
+181ft-148ft

Overall

305

Males

280

M18-39

280

30K→20M

18.6 - 20.0 mi

Top 2%
×5story building
+64ft-50ft

Overall

524

Males

490

M18-39

490

20M→21M

20.0 - 21.0 mi

Top 2%
×8story building
+106ft-24ft

Overall

530

Males

496

M18-39

496

21M→35K

21.0 - 21.8 mi

Top 4%
×7story building
+17ft-86ft

Overall

981

Males

931

M18-39

931

35K→23M

21.8 - 23.0 mi

Top 5%
×5story building
+23ft-63ft

Overall

1429

Males

1356

M18-39

1356

23M→24M

23.0 - 24.0 mi

Top 6%
×6story building
+12ft-82ft

Overall

1712

Males

1613

M18-39

1613

24M→40K

24.0 - 24.9 mi

Top 7%
×1story
+6ft-20ft

Overall

1765

Males

1660

M18-39

1660

40K→25.2M

24.9 - 25.2 mi

Top 10%
×1story
+13ft-16ft

Overall

2628

Males

2414

M18-39

2414

25.2M→Finish

25.2 - 26.2 mi

Top 12%
×2story building
+22ft-21ft

Overall

3157

Males

2834

M18-39

2834

Passing Analysis

Category:
Athletes Passed
55
Passed By
218
Net Change
-163
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#170
5K → 10K165+11#170#159
10K → 15K529-24#159#183
15K → 20K513-8#183#191
20K → Half110#191#191
Half → 25K510-5#191#196
25K → 30K910-1#196#197
30K → 20M114-13#197#210
20M → 21M317-14#210#224
21M → 35K116-15#224#239
35K → 23M026-26#239#265
23M → 24M215-13#265#278
24M → 40K420-16#278#294
40K → 25.2M014-14#294#308
25.2M → Finish328-25#308#333
TOTALS55218-163
📊

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