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BOSTON MARATHON 2024

Robert Koslow

Bib: 4517•M

NY

0:00
0:00
/ mi
Masters
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Overall
#0 / 25550
Top 11%
Gender (Male)
#0 / 14578
Top 19%
Masters (Masters Men)
#0 / 9729
Top 8%
Division (M40-44)
#0 / 2009
Top 23%
Race Day Weather
55°/45°F
scattered clouds

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
19:42
Rank: #2339
Start → 5K
19:42 | 6:20/mi
10K· 6.21 mi
39:27
Rank: #2251 (+88)
5K → 10K
19:45 | 6:21/mi
15K· 9.32 mi
59:14
Rank: #2164 (+87)
10K → 15K
19:47 | 6:22/mi
20K· 12.43 mi
1:19:29
Rank: #2150 (+14)
15K → 20K
20:15 | 6:31/mi
Half· 13.11 mi
1:23:50
Rank: #2129 (+21)
20K → Half
4:21 | 6:23/mi
25K· 15.53 mi
1:39:39
Rank: #2038 (+91)
Half → 25K
15:49 | 6:31/mi
30K· 18.64 mi
2:00:51
Rank: #1972 (+66)
25K → 30K
21:12 | 6:49/mi
20M
2:10:21
Rank: #1967 (+5)
30K → 20M
9:30 | 6:59/mi
21M
2:17:37
Rank: #1906 (+61)
20M → 21M
7:16 | 7:16/mi
35K· 21.75 mi
2:22:39
Rank: #1883 (+23)
21M → 35K
5:02 | 6:44/mi
23M
2:31:19
Rank: #1818 (+65)
35K → 23M
8:40 | 6:55/mi
24M
2:38:11
Rank: #1770 (+48)
23M → 24M
6:52 | 6:52/mi
40K· 24.85 mi
2:44:19
Rank: #1765 (+5)
24M → 40K
6:08 | 7:10/mi
25.2M
2:47:16
Rank: #1787 (-22)
40K → 25.2M
2:57 | 8:33/mi
Finish· 26.22 mi
3:00:20
Rank: #2933 (-1146)
25.2M → Finish
13:04 | 12:49/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:23:50
Pace6:24 /mi
2nd Half
Distance13.11 mi
Time1:36:30
Pace7:22 /mi
📊Positive Split: 15.1% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:22:3319:426:2019:42
6:20
-
10K
6.21 mi10:42:1839:276:2119:45
6:21
+0:01
15K
9.32 mi11:02:0559:146:2119:47
6:22
+0:01
20K
12.43 mi11:22:201:19:296:2420:15
6:31
+0:09
Half
13.11 mi11:26:411:23:506:244:21
6:23
-0:08
25K
15.53 mi11:42:301:39:396:2515:49
6:31
+0:08
30K
18.64 mi12:03:422:00:516:2921:12
6:49
+0:18
20M
20.00 mi12:13:122:10:216:319:30
6:59
+0:10
21M
21.00 mi12:20:282:17:376:337:16
7:16
+0:17
35K
21.75 mi12:25:302:22:396:345:02
6:44
-0:32
23M
23.00 mi12:34:102:31:196:358:40
6:55
+0:11
24M
24.00 mi12:41:022:38:116:356:52
6:52
-0:03
40K
24.85 mi12:47:102:44:196:376:08
7:10
+0:18
25.2M
25.20 mi12:50:072:47:166:382:57
8:33
+1:23
Finish
26.22 mi13:03:113:00:206:5313:04
12:49
+4:16

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

6:20 /mi

Average Pace

6:53 /mi

Slowest Pace

12:49 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

0:00

0% of race

Time at Steady Pace

2:44:19

91% of race

Time at Slower Pace

16:01

9% of race

Average Pace: 6:53 /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 mi10:22:3319:426:2019:42
6:20
#2339
10K
6.21 mi10:42:1839:276:2119:45
6:21
#2251
15K
9.32 mi11:02:0559:146:2119:47
6:22
#2164
20K
12.43 mi11:22:201:19:296:2420:15
6:31
#2150
Half
13.11 mi11:26:411:23:506:244:21
6:23
#2129
25K
15.53 mi11:42:301:39:396:2515:49
6:31
#2038
30K
18.64 mi12:03:422:00:516:2921:12
6:49
#1972
20M
20.00 mi12:13:122:10:216:319:30
6:59
#1967
21M
21.00 mi12:20:282:17:376:337:16
7:16
#1906
35K
21.75 mi12:25:302:22:396:345:02
6:44
#1883
23M
23.00 mi12:34:102:31:196:358:40
6:55
#1818
24M
24.00 mi12:41:022:38:116:356:52
6:52
#1770
40K
24.85 mi12:47:102:44:196:376:08
7:10
#1765
25.2M
25.20 mi12:50:072:47:166:382:57
8:33
#1787
Finish
26.22 mi13:03:113:00:206:5313:04
12:49
#2933
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM40-44Seg. OverallSeg. MalesSeg. M40-44
5K3.11 mi3.11 mi2339225822582035(Top 8%)1968(Top 13%)1968(Top 98%)
10K6.21 mi3.10 mi2251+882176+822176+822205(Top 9%)2126(Top 15%)2126(Top 106%)
15K9.32 mi3.11 mi2164+872092+842092+842035(Top 8%)1968(Top 13%)1968(Top 98%)
20K12.43 mi3.11 mi2150+142077+152077+152267(Top 9%)2175(Top 15%)2175(Top 108%)
Half13.11 mi0.68 mi2129+212056+212056+212040(Top 8%)1962(Top 13%)1962(Top 98%)
25K15.53 mi2.42 mi2038+911969+871969+871878(Top 7%)1804(Top 12%)1804(Top 90%)
30K18.64 mi3.11 mi1972+661904+651904+652039(Top 8%)1931(Top 13%)1931(Top 96%)
20M20.00 mi1.36 mi1967+51896+81896+82346(Top 9%)2187(Top 15%)2187(Top 109%)
21M21.00 mi1.00 mi1906+611837+591837+591778(Top 7%)1664(Top 11%)1664(Top 83%)
35K21.75 mi0.75 mi1883+231811+261811+262051(Top 8%)1890(Top 13%)1890(Top 94%)
23M23.00 mi1.25 mi1818+651746+651746+651699(Top 7%)1572(Top 11%)1572(Top 78%)
24M24.00 mi1.00 mi1770+481696+501696+501920(Top 8%)1738(Top 12%)1738(Top 87%)
40K24.85 mi0.85 mi1765+51690+61690+62423(Top 9%)2119(Top 15%)2119(Top 105%)
25.2M25.20 mi0.35 mi1787-221707-171707-174780(Top 19%)3587(Top 25%)3587(Top 179%)
Finish26.22 mi1.02 mi2933-11462733-10262733-102624204(Top 95%)13684(Top 94%)13684(Top 681%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 8%
×21stories
+97ft-345ft

Overall

2035

Males

1968

M40-44

1968

5K→10K

3.1 - 6.2 mi

Top 9%
×5stories
+79ft-138ft

Overall

2205

Males

2126

M40-44

2126

10K→15K

6.2 - 9.3 mi

Top 8%
×3stories
+67ft-78ft

Overall

2035

Males

1968

M40-44

1968

15K→20K

9.3 - 12.4 mi

Top 9%
×5stories
+106ft-86ft

Overall

2267

Males

2175

M40-44

2175

20K→Half

12.4 - 13.1 mi

Top 8%
×2stories
+19ft-37ft

Overall

2040

Males

1962

M40-44

1962

Half→25K

13.1 - 15.5 mi

Top 7%
×4stories
+66ft-88ft

Overall

1878

Males

1804

M40-44

1804

25K→30K

15.5 - 18.6 mi

Top 8%
×9stories
+181ft-148ft

Overall

2039

Males

1931

M40-44

1931

30K→20M

18.6 - 20.0 mi

Top 9%
×5stories
+64ft-50ft

Overall

2346

Males

2187

M40-44

2187

20M→21M

20.0 - 21.0 mi

Top 7%
×8stories
+106ft-24ft

Overall

1778

Males

1664

M40-44

1664

21M→35K

21.0 - 21.8 mi

Top 8%
×7stories
+17ft-86ft

Overall

2051

Males

1890

M40-44

1890

35K→23M

21.8 - 23.0 mi

Top 7%
×5stories
+23ft-63ft

Overall

1699

Males

1572

M40-44

1572

23M→24M

23.0 - 24.0 mi

Top 8%
×6stories
+12ft-82ft

Overall

1920

Males

1738

M40-44

1738

24M→40K

24.0 - 24.9 mi

Top 9%
×1story
+6ft-20ft

Overall

2423

Males

2119

M40-44

2119

40K→25.2M

24.9 - 25.2 mi

Top 19%
×1story
+13ft-16ft

Overall

4780

Males

3587

M40-44

3587

25.2M→Finish

25.2 - 26.2 mi

Top 95%
×2stories
+22ft-21ft

Overall

24204

Males

13684

M40-44

13684

Passing Analysis

Category:
Athletes Passed
1026
Passed By
1620
Net Change
-594
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#2339
5K → 10K16173+88#2339#2251
10K → 15K12437+87#2251#2164
15K → 20K9985+14#2164#2150
20K → Half265+21#2150#2129
Half → 25K11322+91#2129#2038
25K → 30K14175+66#2038#1972
30K → 20M5449+5#1972#1967
20M → 21M8221+61#1967#1906
21M → 35K3815+23#1906#1883
35K → 23M8621+65#1883#1818
23M → 24M6214+48#1818#1770
24M → 40K2924+5#1770#1765
40K → 25.2M1032-22#1765#1787
25.2M → Finish11147-1146#1787#2933
TOTALS10261620-594
📊

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