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BOSTON MARATHON 2023

Karl Fredrik Ahlgren

Bib: 27538•M

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

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
10:00/mi
31:05
↑ 97↓ 3451.5%
10K· 6.21 mi
9:33/mi
1:00:45
↑ 79↓ 1380.4%
15K· 9.32 mi
9:16/mi
1:29:32
↑ 67↓ 78
20K· 12.43 mi
9:18/mi
1:58:27
↑ 106↓ 860.1%
Half· 13.11 mi
9:16/mi
2:04:46
↑ 19↓ 370.5%
25K· 15.53 mi
9:36/mi
2:28:02
↑ 66↓ 880.2%
30K· 18.64 mi
9:52/mi
2:58:40
↑ 181↓ 1480.2%
20M
9:52/mi
3:12:05
↑ 64↓ 500.2%
21M
10:24/mi
3:22:29
↑ 106↓ 241.6%
35K· 21.75 mi
9:40/mi
3:29:43
↑ 17↓ 861.7%
23M
9:55/mi
3:42:08
↑ 23↓ 630.6%
24M
9:47/mi
3:51:55
↓ 821.3%
40K· 24.85 mi
9:41/mi
4:00:12
↓ 200.3%
25.2M
10:23/mi
4:03:47
↑ 13↓ 160.2%
Finish· 26.22 mi
9:30/mi
4:13:28
↑ 22↓ 21

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time2:04:46
Pace9:31 /mi
2nd Half
Distance13.11 mi
Time2:08:42
Pace9:49 /mi
📊Positive Split: 3.2% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:48:1131:0510:0031:05
10:00
-
10K
6.21 mi12:17:511:00:459:4729:40
9:33
-0:27
15K
9.32 mi12:46:381:29:329:3628:47
9:16
-0:17
20K
12.43 mi13:15:331:58:279:3228:55
9:18
+0:02
Half
13.11 mi13:21:522:04:469:316:19
9:16
-0:02
25K
15.53 mi13:45:082:28:029:3223:16
9:36
+0:20
30K
18.64 mi14:15:462:58:409:3530:38
9:52
+0:16
20M
20.00 mi14:29:113:12:059:3613:25
9:52
0:00
21M
21.00 mi14:39:353:22:299:3910:24
10:24
+0:32
35K
21.75 mi14:46:493:29:439:397:14
9:40
-0:44
23M
23.00 mi14:59:143:42:089:3912:25
9:55
+0:15
24M
24.00 mi15:09:013:51:559:409:47
9:47
-0:08
40K
24.85 mi15:17:184:00:129:408:17
9:41
-0:06
25.2M
25.20 mi15:20:534:03:479:403:35
10:23
+0:42
Finish
26.22 mi15:30:344:13:289:409:41
9:30
-0:53

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

9:16 /mi

Average Pace

9:40 /mi

Slowest Pace

10:24 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

3:59:29

94% of race

Time at Steady Pace

13:59

6% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 9:40 /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 mi11:48:1131:0510:0031:05
10:00
#23445
10K
6.21 mi12:17:511:00:459:4729:40
9:33
#23112
15K
9.32 mi12:46:381:29:329:3628:47
9:16
#22609
20K
12.43 mi13:15:331:58:279:3228:55
9:18
#22215
Half
13.11 mi13:21:522:04:469:316:19
9:16
#22162
25K
15.53 mi13:45:082:28:029:3223:16
9:36
#21973
30K
18.64 mi14:15:462:58:409:3530:38
9:52
#21702
20M
20.00 mi14:29:113:12:059:3613:25
9:52
#21598
21M
21.00 mi14:39:353:22:299:3910:24
10:24
#21476
35K
21.75 mi14:46:493:29:439:397:14
9:40
#21434
23M
23.00 mi14:59:143:42:089:3912:25
9:55
#21320
24M
24.00 mi15:09:013:51:559:409:47
9:47
#21255
40K
24.85 mi15:17:184:00:129:408:17
9:41
#21157
25.2M
25.20 mi15:20:534:03:479:403:35
10:23
#21118
Finish
26.22 mi15:30:344:13:289:409:41
9:30
#21085
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM50-54Seg. OverallSeg. MalesSeg. M50-54
5K3.11 mi3.11 mi23445137991379921522(Top 81%)12986(Top 86%)12986(Top 633%)
10K6.21 mi3.10 mi23112+33313661+13813661+13822644(Top 85%)13454(Top 89%)13454(Top 656%)
15K9.32 mi3.11 mi22609+50313441+22013441+22021522(Top 81%)12986(Top 86%)12986(Top 633%)
20K12.43 mi3.11 mi22215+39413247+19413247+19420987(Top 79%)12742(Top 84%)12742(Top 621%)
Half13.11 mi0.68 mi22162+5313222+2513222+2521332(Top 80%)12883(Top 85%)12883(Top 628%)
25K15.53 mi2.42 mi21973+18913140+8213140+8221121(Top 79%)12764(Top 84%)12764(Top 622%)
30K18.64 mi3.11 mi21702+27113012+12813012+12820639(Top 78%)12488(Top 82%)12488(Top 609%)
20M20.00 mi1.36 mi21598+10412959+5312959+5320092(Top 75%)12159(Top 80%)12159(Top 593%)
21M21.00 mi1.00 mi21476+12212888+7112888+7119270(Top 72%)11753(Top 77%)11753(Top 573%)
35K21.75 mi0.75 mi21434+4212860+2812860+2820364(Top 76%)12196(Top 80%)12196(Top 594%)
23M23.00 mi1.25 mi21320+11412792+6812792+6819733(Top 74%)11900(Top 78%)11900(Top 580%)
24M24.00 mi1.00 mi21255+6512751+4112751+4120161(Top 76%)12081(Top 80%)12081(Top 589%)
40K24.85 mi0.85 mi21157+9812694+5712694+5718980(Top 71%)11480(Top 76%)11480(Top 559%)
25.2M25.20 mi0.35 mi21118+3912672+2212672+2218737(Top 70%)11365(Top 75%)11365(Top 554%)
Finish26.22 mi1.02 mi21085+3312645+2712645+2720128(Top 76%)12036(Top 79%)12036(Top 587%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 81%
×21story building
+97ft-345ft

Overall

21522

Males

12986

M50-54

12986

5K→10K

3.1 - 6.2 mi

Top 85%
×5story building
+79ft-138ft

Overall

22644

Males

13454

M50-54

13454

10K→15K

6.2 - 9.3 mi

Top 81%
×3story building
+67ft-78ft

Overall

21522

Males

12986

M50-54

12986

15K→20K

9.3 - 12.4 mi

Top 79%
×5story building
+106ft-86ft

Overall

20987

Males

12742

M50-54

12742

20K→Half

12.4 - 13.1 mi

Top 80%
×2story building
+19ft-37ft

Overall

21332

Males

12883

M50-54

12883

Half→25K

13.1 - 15.5 mi

Top 79%
×4story building
+66ft-88ft

Overall

21121

Males

12764

M50-54

12764

25K→30K

15.5 - 18.6 mi

Top 78%
×9story building
+181ft-148ft

Overall

20639

Males

12488

M50-54

12488

30K→20M

18.6 - 20.0 mi

Top 75%
×5story building
+64ft-50ft

Overall

20092

Males

12159

M50-54

12159

20M→21M

20.0 - 21.0 mi

Top 72%
×8story building
+106ft-24ft

Overall

19270

Males

11753

M50-54

11753

21M→35K

21.0 - 21.8 mi

Top 76%
×7story building
+17ft-86ft

Overall

20364

Males

12196

M50-54

12196

35K→23M

21.8 - 23.0 mi

Top 74%
×5story building
+23ft-63ft

Overall

19733

Males

11900

M50-54

11900

23M→24M

23.0 - 24.0 mi

Top 76%
×6story building
+12ft-82ft

Overall

20161

Males

12081

M50-54

12081

24M→40K

24.0 - 24.9 mi

Top 71%
×1story
+6ft-20ft

Overall

18980

Males

11480

M50-54

11480

40K→25.2M

24.9 - 25.2 mi

Top 70%
×1story
+13ft-16ft

Overall

18737

Males

11365

M50-54

11365

25.2M→Finish

25.2 - 26.2 mi

Top 76%
×2story building
+22ft-21ft

Overall

20128

Males

12036

M50-54

12036

Passing Analysis

Category:
Athletes Passed
2616
Passed By
256
Net Change
+2360
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#23445
5K → 10K41784+333#23445#23112
10K → 15K51411+503#23112#22609
15K → 20K40410+394#22609#22215
20K → Half574+53#22215#22162
Half → 25K20415+189#22162#21973
25K → 30K30231+271#21973#21702
30K → 20M1128+104#21702#21598
20M → 21M13513+122#21598#21476
21M → 35K5614+42#21476#21434
35K → 23M12612+114#21434#21320
23M → 24M8116+65#21320#21255
24M → 40K1057+98#21255#21157
40K → 25.2M412+39#21157#21118
25.2M → Finish6229+33#21118#21085
TOTALS2616256+2360
📊

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