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BOSTON MARATHON 2023

Keith Shields

Bib: 25943•M

MA

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Gender (Male)
#0 / 15176
Masters (Masters Men)
#0 / 9891
Division (M50-54)
#0 / 2052
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
26:41
Rank: #18154
Start → 5K
26:41 | 8:35/mi
10K· 6.21 mi
54:13
Rank: #19280 (-1126)
5K → 10K
27:32 | 8:52/mi
15K· 9.32 mi
1:22:18
Rank: #19760 (-480)
10K → 15K
28:05 | 9:02/mi
20K· 12.43 mi
1:49:23
Rank: #19323 (+437)
15K → 20K
27:05 | 8:43/mi
Half· 13.11 mi
1:55:17
Rank: #19283 (+40)
20K → Half
5:54 | 8:39/mi
25K· 15.53 mi
2:17:17
Rank: #19292 (-9)
Half → 25K
22:00 | 9:04/mi
30K· 18.64 mi
2:46:53
Rank: #19365 (-73)
25K → 30K
29:36 | 9:32/mi
20M
3:00:13
Rank: #19415 (-50)
30K → 20M
13:20 | 9:49/mi
21M
3:11:18
Rank: #19545 (-130)
20M → 21M
11:05 | 11:05/mi
35K· 21.75 mi
3:18:20
Rank: #19563 (-18)
21M → 35K
7:02 | 9:24/mi
23M
3:31:02
Rank: #19633 (-70)
35K → 23M
12:42 | 10:09/mi
24M
3:40:24
Rank: #19594 (+39)
23M → 24M
9:22 | 9:22/mi
40K· 24.85 mi
3:48:51
Rank: #19605 (-11)
24M → 40K
8:27 | 9:53/mi
25.2M
3:52:36
Rank: #19620 (-15)
40K → 25.2M
3:45 | 10:52/mi
Finish· 26.22 mi
4:01:56
Rank: #19599 (+21)
25.2M → Finish
9:20 | 9:10/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:55:17
Pace8:48 /mi
2nd Half
Distance13.11 mi
Time2:06:39
Pace9:40 /mi
📊Positive Split: 9.9% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:42:3626:418:3526:41
8:35
-
10K
6.21 mi12:10:0854:138:4427:32
8:52
+0:17
15K
9.32 mi12:38:131:22:188:5028:05
9:02
+0:10
20K
12.43 mi13:05:181:49:238:4827:05
8:43
-0:19
Half
13.11 mi13:11:121:55:178:485:54
8:39
-0:04
25K
15.53 mi13:33:122:17:178:5022:00
9:04
+0:25
30K
18.64 mi14:02:482:46:538:5729:36
9:32
+0:28
20M
20.00 mi14:16:083:00:139:0113:20
9:49
+0:17
21M
21.00 mi14:27:133:11:189:0711:05
11:05
+1:16
35K
21.75 mi14:34:153:18:209:077:02
9:24
-1:41
23M
23.00 mi14:46:573:31:029:1112:42
10:09
+0:45
24M
24.00 mi14:56:193:40:249:119:22
9:22
-0:47
40K
24.85 mi15:04:463:48:519:128:27
9:53
+0:31
25.2M
25.20 mi15:08:313:52:369:143:45
10:52
+0:59
Finish
26.22 mi15:17:514:01:569:149:20
9:10
-1:42

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

8:35 /mi

Average Pace

9:14 /mi

Slowest Pace

11:05 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:27:12

36% of race

Time at Steady Pace

1:45:25

44% of race

Time at Slower Pace

49:19

20% of race

Average Pace: 9:14 /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 mi11:42:3626:418:3526:41
8:35
#18154
10K
6.21 mi12:10:0854:138:4427:32
8:52
#19280
15K
9.32 mi12:38:131:22:188:5028:05
9:02
#19760
20K
12.43 mi13:05:181:49:238:4827:05
8:43
#19323
Half
13.11 mi13:11:121:55:178:485:54
8:39
#19283
25K
15.53 mi13:33:122:17:178:5022:00
9:04
#19292
30K
18.64 mi14:02:482:46:538:5729:36
9:32
#19365
20M
20.00 mi14:16:083:00:139:0113:20
9:49
#19415
21M
21.00 mi14:27:133:11:189:0711:05
11:05
#19545
35K
21.75 mi14:34:153:18:209:077:02
9:24
#19563
23M
23.00 mi14:46:573:31:029:1112:42
10:09
#19633
24M
24.00 mi14:56:193:40:249:119:22
9:22
#19594
40K
24.85 mi15:04:463:48:519:128:27
9:53
#19605
25.2M
25.20 mi15:08:313:52:369:143:45
10:52
#19620
Finish
26.22 mi15:17:514:01:569:149:20
9:10
#19599
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM50-54Seg. OverallSeg. MalesSeg. M50-54
5K3.11 mi3.11 mi18154114821148220665(Top 78%)12597(Top 83%)12597(Top 614%)
10K6.21 mi3.10 mi19280-112611934-45211934-45220227(Top 76%)12371(Top 82%)12371(Top 603%)
15K9.32 mi3.11 mi19760-48012143-20912143-20920665(Top 78%)12597(Top 83%)12597(Top 614%)
20K12.43 mi3.11 mi19323+43711982+16111982+16118222(Top 68%)11576(Top 76%)11576(Top 564%)
Half13.11 mi0.68 mi19283+4011972+1011972+1018588(Top 70%)11749(Top 77%)11749(Top 573%)
25K15.53 mi2.42 mi19292-911973-111973-119295(Top 72%)11971(Top 79%)11971(Top 583%)
30K18.64 mi3.11 mi19365-7311989-1611989-1619524(Top 73%)12014(Top 79%)12014(Top 585%)
20M20.00 mi1.36 mi19415-5011995-611995-619883(Top 75%)12071(Top 80%)12071(Top 588%)
21M21.00 mi1.00 mi19545-13012039-4412039-4420987(Top 79%)12510(Top 82%)12510(Top 610%)
35K21.75 mi0.75 mi19563-1812046-712046-719528(Top 73%)11834(Top 78%)11834(Top 577%)
23M23.00 mi1.25 mi19633-7012071-2512071-2520409(Top 77%)12207(Top 80%)12207(Top 595%)
24M24.00 mi1.00 mi19594+3912037+3412037+3418709(Top 70%)11408(Top 75%)11408(Top 556%)
40K24.85 mi0.85 mi19605-11120371203719632(Top 74%)11759(Top 77%)11759(Top 573%)
25.2M25.20 mi0.35 mi19620-1512035+212035+220136(Top 76%)11982(Top 79%)11982(Top 584%)
Finish26.22 mi1.02 mi19599+2112017+1812017+1818725(Top 70%)11415(Top 75%)11415(Top 556%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 78%
×21stories
+97ft-345ft

Overall

20665

Males

12597

M50-54

12597

5K→10K

3.1 - 6.2 mi

Top 76%
×5stories
+79ft-138ft

Overall

20227

Males

12371

M50-54

12371

10K→15K

6.2 - 9.3 mi

Top 78%
×3stories
+67ft-78ft

Overall

20665

Males

12597

M50-54

12597

15K→20K

9.3 - 12.4 mi

Top 68%
×5stories
+106ft-86ft

Overall

18222

Males

11576

M50-54

11576

20K→Half

12.4 - 13.1 mi

Top 70%
×2stories
+19ft-37ft

Overall

18588

Males

11749

M50-54

11749

Half→25K

13.1 - 15.5 mi

Top 72%
×4stories
+66ft-88ft

Overall

19295

Males

11971

M50-54

11971

25K→30K

15.5 - 18.6 mi

Top 73%
×9stories
+181ft-148ft

Overall

19524

Males

12014

M50-54

12014

30K→20M

18.6 - 20.0 mi

Top 75%
×5stories
+64ft-50ft

Overall

19883

Males

12071

M50-54

12071

20M→21M

20.0 - 21.0 mi

Top 79%
×8stories
+106ft-24ft

Overall

20987

Males

12510

M50-54

12510

21M→35K

21.0 - 21.8 mi

Top 73%
×7stories
+17ft-86ft

Overall

19528

Males

11834

M50-54

11834

35K→23M

21.8 - 23.0 mi

Top 77%
×5stories
+23ft-63ft

Overall

20409

Males

12207

M50-54

12207

23M→24M

23.0 - 24.0 mi

Top 70%
×6stories
+12ft-82ft

Overall

18709

Males

11408

M50-54

11408

24M→40K

24.0 - 24.9 mi

Top 74%
×1story
+6ft-20ft

Overall

19632

Males

11759

M50-54

11759

40K→25.2M

24.9 - 25.2 mi

Top 76%
×1story
+13ft-16ft

Overall

20136

Males

11982

M50-54

11982

25.2M→Finish

25.2 - 26.2 mi

Top 70%
×2stories
+22ft-21ft

Overall

18725

Males

11415

M50-54

11415

Passing Analysis

Category:
Athletes Passed
1261
Passed By
2706
Net Change
-1445
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#18154
5K → 10K591185-1126#18154#19280
10K → 15K57537-480#19280#19760
15K → 20K45619+437#19760#19323
20K → Half477+40#19323#19283
Half → 25K118127-9#19283#19292
25K → 30K134207-73#19292#19365
30K → 20M67117-50#19365#19415
20M → 21M46176-130#19415#19545
21M → 35K3553-18#19545#19563
35K → 23M50120-70#19563#19633
23M → 24M7536+39#19633#19594
24M → 40K3445-11#19594#19605
40K → 25.2M2641-15#19605#19620
25.2M → Finish5736+21#19620#19599
TOTALS12612706-1445
📊

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