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BOSTON MARATHON 2023

Derek Siebert

Bib: 9521•M

WA

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Top 30%
Gender (Male)
#0 / 15176
Top 44%
Masters (Masters Men)
#0 / 9891
Top 31%
Division (M40-44)
#0 / 2241
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
22:18
Rank: #7362
Start → 5K
22:18 | 7:11/mi
10K· 6.21 mi
44:18
Rank: #7295 (+67)
5K → 10K
22:00 | 7:05/mi
15K· 9.32 mi
1:06:30
Rank: #7325 (-30)
10K → 15K
22:12 | 7:09/mi
20K· 12.43 mi
1:28:52
Rank: #7231 (+94)
15K → 20K
22:22 | 7:12/mi
Half· 13.11 mi
1:33:45
Rank: #7242 (-11)
20K → Half
4:53 | 7:09/mi
25K· 15.53 mi
1:51:24
Rank: #7200 (+42)
Half → 25K
17:39 | 7:17/mi
30K· 18.64 mi
2:14:26
Rank: #7055 (+145)
25K → 30K
23:02 | 7:25/mi
20M
2:24:37
Rank: #7006 (+49)
30K → 20M
10:11 | 7:30/mi
21M
2:32:35
Rank: #6957 (+49)
20M → 21M
7:58 | 7:58/mi
35K· 21.75 mi
2:38:08
Rank: #6958 (-1)
21M → 35K
5:33 | 7:25/mi
23M
2:48:19
Rank: #7140 (-182)
35K → 23M
10:11 | 8:08/mi
24M
2:57:41
Rank: #7643 (-503)
23M → 24M
9:22 | 9:22/mi
40K· 24.85 mi
3:04:34
Rank: #7756 (-113)
24M → 40K
6:53 | 8:03/mi
25.2M
3:07:32
Rank: #7775 (-19)
40K → 25.2M
2:58 | 8:36/mi
Finish· 26.22 mi
3:15:34
Rank: #7889 (-114)
25.2M → Finish
8:02 | 7:53/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:33:45
Pace7:09 /mi
2nd Half
Distance13.11 mi
Time1:41:49
Pace7:46 /mi
📊Positive Split: 8.6% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:47:4922:187:1122:18
7:11
-
10K
6.21 mi11:09:4944:187:0822:00
7:05
-0:06
15K
9.32 mi11:32:011:06:307:0822:12
7:09
+0:04
20K
12.43 mi11:54:231:28:527:0922:22
7:12
+0:03
Half
13.11 mi11:59:161:33:457:094:53
7:09
-0:03
25K
15.53 mi12:16:551:51:247:1017:39
7:17
+0:08
30K
18.64 mi12:39:572:14:267:1323:02
7:25
+0:08
20M
20.00 mi12:50:082:24:377:1410:11
7:30
+0:05
21M
21.00 mi12:58:062:32:357:167:58
7:58
+0:28
35K
21.75 mi13:03:392:38:087:165:33
7:25
-0:33
23M
23.00 mi13:13:502:48:197:1910:11
8:08
+0:43
24M
24.00 mi13:23:122:57:417:249:22
9:22
+1:14
40K
24.85 mi13:30:053:04:347:266:53
8:03
-1:19
25.2M
25.20 mi13:33:033:07:327:272:58
8:36
+0:33
Finish
26.22 mi13:41:053:15:347:288:02
7:53
-0:43

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

7:05 /mi

Average Pace

7:28 /mi

Slowest Pace

9:22 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

22:00

11% of race

Time at Steady Pace

2:08:10

66% of race

Time at Slower Pace

45:24

23% of race

Average Pace: 7:28 /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 mi10:47:4922:187:1122:18
7:11
#7362
10K
6.21 mi11:09:4944:187:0822:00
7:05
#7295
15K
9.32 mi11:32:011:06:307:0822:12
7:09
#7325
20K
12.43 mi11:54:231:28:527:0922:22
7:12
#7231
Half
13.11 mi11:59:161:33:457:094:53
7:09
#7242
25K
15.53 mi12:16:551:51:247:1017:39
7:17
#7200
30K
18.64 mi12:39:572:14:267:1323:02
7:25
#7055
20M
20.00 mi12:50:082:24:377:1410:11
7:30
#7006
21M
21.00 mi12:58:062:32:357:167:58
7:58
#6957
35K
21.75 mi13:03:392:38:087:165:33
7:25
#6958
23M
23.00 mi13:13:502:48:197:1910:11
8:08
#7140
24M
24.00 mi13:23:122:57:417:249:22
9:22
#7643
40K
24.85 mi13:30:053:04:347:266:53
8:03
#7756
25.2M
25.20 mi13:33:033:07:327:272:58
8:36
#7775
Finish
26.22 mi13:41:053:15:347:288:02
7:53
#7889
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM40-44Seg. OverallSeg. MalesSeg. M40-44
5K3.11 mi3.11 mi7362654965497438(Top 28%)6555(Top 43%)6555(Top 293%)
10K6.21 mi3.10 mi7295+676479+706479+707320(Top 27%)6471(Top 43%)6471(Top 289%)
15K9.32 mi3.11 mi7325-306495-166495-167438(Top 28%)6555(Top 43%)6555(Top 293%)
20K12.43 mi3.11 mi7231+946417+786417+787095(Top 27%)6282(Top 41%)6282(Top 280%)
Half13.11 mi0.68 mi7242-116424-76424-77550(Top 28%)6609(Top 44%)6609(Top 295%)
25K15.53 mi2.42 mi7200+426385+396385+397161(Top 27%)6263(Top 41%)6263(Top 279%)
30K18.64 mi3.11 mi7055+1456256+1296256+1296682(Top 25%)5856(Top 39%)5856(Top 261%)
20M20.00 mi1.36 mi7006+496212+446212+446747(Top 25%)5807(Top 38%)5807(Top 259%)
21M21.00 mi1.00 mi6957+496160+526160+527132(Top 27%)5948(Top 39%)5948(Top 265%)
35K21.75 mi0.75 mi6958-16153+76153+77899(Top 30%)6434(Top 42%)6434(Top 287%)
23M23.00 mi1.25 mi7140-1826248-956248-9510669(Top 40%)7793(Top 51%)7793(Top 348%)
24M24.00 mi1.00 mi7643-5036563-3156563-31518691(Top 70%)11390(Top 75%)11390(Top 508%)
40K24.85 mi0.85 mi7756-1136618-556618-5510326(Top 39%)7493(Top 49%)7493(Top 334%)
25.2M25.20 mi0.35 mi7775-196616+26616+210082(Top 38%)7316(Top 48%)7316(Top 326%)
Finish26.22 mi1.02 mi7889-1146669-536669-5311244(Top 42%)7901(Top 52%)7901(Top 353%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 28%
×21stories
+97ft-345ft

Overall

7438

Males

6555

M40-44

6555

5K→10K

3.1 - 6.2 mi

Top 27%
×5stories
+79ft-138ft

Overall

7320

Males

6471

M40-44

6471

10K→15K

6.2 - 9.3 mi

Top 28%
×3stories
+67ft-78ft

Overall

7438

Males

6555

M40-44

6555

15K→20K

9.3 - 12.4 mi

Top 27%
×5stories
+106ft-86ft

Overall

7095

Males

6282

M40-44

6282

20K→Half

12.4 - 13.1 mi

Top 28%
×2stories
+19ft-37ft

Overall

7550

Males

6609

M40-44

6609

Half→25K

13.1 - 15.5 mi

Top 27%
×4stories
+66ft-88ft

Overall

7161

Males

6263

M40-44

6263

25K→30K

15.5 - 18.6 mi

Top 25%
×9stories
+181ft-148ft

Overall

6682

Males

5856

M40-44

5856

30K→20M

18.6 - 20.0 mi

Top 25%
×5stories
+64ft-50ft

Overall

6747

Males

5807

M40-44

5807

20M→21M

20.0 - 21.0 mi

Top 27%
×8stories
+106ft-24ft

Overall

7132

Males

5948

M40-44

5948

21M→35K

21.0 - 21.8 mi

Top 30%
×7stories
+17ft-86ft

Overall

7899

Males

6434

M40-44

6434

35K→23M

21.8 - 23.0 mi

Top 40%
×5stories
+23ft-63ft

Overall

10669

Males

7793

M40-44

7793

23M→24M

23.0 - 24.0 mi

Top 70%
×6stories
+12ft-82ft

Overall

18691

Males

11390

M40-44

11390

24M→40K

24.0 - 24.9 mi

Top 39%
×1story
+6ft-20ft

Overall

10326

Males

7493

M40-44

7493

40K→25.2M

24.9 - 25.2 mi

Top 38%
×1story
+13ft-16ft

Overall

10082

Males

7316

M40-44

7316

25.2M→Finish

25.2 - 26.2 mi

Top 42%
×2stories
+22ft-21ft

Overall

11244

Males

7901

M40-44

7901

Passing Analysis

Category:
Athletes Passed
1161
Passed By
1688
Net Change
-527
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#7362
5K → 10K251184+67#7362#7295
10K → 15K119149-30#7295#7325
15K → 20K15460+94#7325#7231
20K → Half1223-11#7231#7242
Half → 25K10462+42#7242#7200
25K → 30K19651+145#7200#7055
30K → 20M7829+49#7055#7006
20M → 21M8637+49#7006#6957
21M → 35K3536-1#6957#6958
35K → 23M40222-182#6958#7140
23M → 24M7510-503#7140#7643
24M → 40K32145-113#7643#7756
40K → 25.2M2140-19#7756#7775
25.2M → Finish26140-114#7775#7889
TOTALS11611688-527
📊

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