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BOSTON MARATHON 2023

Ron Kozlin

Bib: 24813•M

FL

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
28:08
Rank: #20675
Start → 5K
28:08 | 9:03/mi
10K· 6.21 mi
56:05
Rank: #20737 (-62)
5K → 10K
27:57 | 9:00/mi
15K· 9.32 mi
1:24:29
Rank: #20860 (-123)
10K → 15K
28:24 | 9:08/mi
20K· 12.43 mi
1:53:12
Rank: #20816 (+44)
15K → 20K
28:43 | 9:15/mi
Half· 13.11 mi
1:59:36
Rank: #20874 (-58)
20K → Half
6:24 | 9:23/mi
25K· 15.53 mi
2:22:57
Rank: #20935 (-61)
Half → 25K
23:21 | 9:38/mi
30K· 18.64 mi
2:54:06
Rank: #20963 (-28)
25K → 30K
31:09 | 10:02/mi
20M
3:07:59
Rank: #20950 (+13)
30K → 20M
13:53 | 10:13/mi
21M
3:18:26
Rank: #20852 (+98)
20M → 21M
10:27 | 10:27/mi
35K· 21.75 mi
3:25:54
Rank: #20859 (-7)
21M → 35K
7:28 | 9:59/mi
23M
3:38:27
Rank: #20795 (+64)
35K → 23M
12:33 | 10:01/mi
24M
3:48:10
Rank: #20750 (+45)
23M → 24M
9:43 | 9:43/mi
40K· 24.85 mi
3:56:39
Rank: #20701 (+49)
24M → 40K
8:29 | 9:55/mi
25.2M
4:00:15
Rank: #20676 (+25)
40K → 25.2M
3:36 | 10:26/mi
Finish· 26.22 mi
4:09:27
Rank: #20588 (+88)
25.2M → Finish
9:12 | 9:02/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:59:36
Pace9:07 /mi
2nd Half
Distance13.11 mi
Time2:09:51
Pace9:54 /mi
📊Positive Split: 8.6% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi11:43:1928:089:0328:08
9:03
-
10K
6.21 mi12:11:1656:059:0227:57
9:00
-0:03
15K
9.32 mi12:39:401:24:299:0428:24
9:08
+0:08
20K
12.43 mi13:08:231:53:129:0728:43
9:15
+0:07
Half
13.11 mi13:14:471:59:369:076:24
9:23
+0:08
25K
15.53 mi13:38:082:22:579:1223:21
9:38
+0:15
30K
18.64 mi14:09:172:54:069:2031:09
10:02
+0:24
20M
20.00 mi14:23:103:07:599:2413:53
10:13
+0:11
21M
21.00 mi14:33:373:18:269:2710:27
10:27
+0:14
35K
21.75 mi14:41:053:25:549:287:28
9:59
-0:28
23M
23.00 mi14:53:383:38:279:3012:33
10:01
+0:02
24M
24.00 mi15:03:213:48:109:309:43
9:43
-0:18
40K
24.85 mi15:11:503:56:399:318:29
9:55
+0:12
25.2M
25.20 mi15:15:264:00:159:323:36
10:26
+0:31
Finish
26.22 mi15:24:384:09:279:319:12
9:02
-1:24

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

9:00 /mi

Average Pace

9:31 /mi

Slowest Pace

10:27 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:41:52

65% of race

Time at Steady Pace

1:27:35

35% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 9:31 /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 mi11:43:1928:089:0328:08
9:03
#20675
10K
6.21 mi12:11:1656:059:0227:57
9:00
#20737
15K
9.32 mi12:39:401:24:299:0428:24
9:08
#20860
20K
12.43 mi13:08:231:53:129:0728:43
9:15
#20816
Half
13.11 mi13:14:471:59:369:076:24
9:23
#20874
25K
15.53 mi13:38:082:22:579:1223:21
9:38
#20935
30K
18.64 mi14:09:172:54:069:2031:09
10:02
#20963
20M
20.00 mi14:23:103:07:599:2413:53
10:13
#20950
21M
21.00 mi14:33:373:18:269:2710:27
10:27
#20852
35K
21.75 mi14:41:053:25:549:287:28
9:59
#20859
23M
23.00 mi14:53:383:38:279:3012:33
10:01
#20795
24M
24.00 mi15:03:213:48:109:309:43
9:43
#20750
40K
24.85 mi15:11:503:56:399:318:29
9:55
#20701
25.2M
25.20 mi15:15:264:00:159:323:36
10:26
#20676
Finish
26.22 mi15:24:384:09:279:319:12
9:02
#20588
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM50-54Seg. OverallSeg. MalesSeg. M50-54
5K3.11 mi3.11 mi20675124421244221106(Top 79%)12793(Top 84%)12793(Top 623%)
10K6.21 mi3.10 mi20737-6212553-11112553-11120857(Top 78%)12649(Top 83%)12649(Top 616%)
15K9.32 mi3.11 mi20860-12312629-7612629-7621106(Top 79%)12793(Top 84%)12793(Top 623%)
20K12.43 mi3.11 mi20816+4412626+312626+320739(Top 78%)12636(Top 83%)12636(Top 616%)
Half13.11 mi0.68 mi20874-5812656-3012656-3021738(Top 82%)13059(Top 86%)13059(Top 636%)
25K15.53 mi2.42 mi20935-6112689-3312689-3321218(Top 80%)12802(Top 84%)12802(Top 624%)
30K18.64 mi3.11 mi20963-2812682+712682+721095(Top 79%)12675(Top 84%)12675(Top 618%)
20M20.00 mi1.36 mi20950+1312663+1912663+1921052(Top 79%)12591(Top 83%)12591(Top 614%)
21M21.00 mi1.00 mi20852+9812604+5912604+5919428(Top 73%)11810(Top 78%)11810(Top 576%)
35K21.75 mi0.75 mi20859-712595+912595+921187(Top 80%)12569(Top 83%)12569(Top 613%)
23M23.00 mi1.25 mi20795+6412561+3412561+3420051(Top 75%)12044(Top 79%)12044(Top 587%)
24M24.00 mi1.00 mi20750+4512523+3812523+3819947(Top 75%)11981(Top 79%)11981(Top 584%)
40K24.85 mi0.85 mi20701+4912492+3112492+3119748(Top 74%)11808(Top 78%)11808(Top 575%)
25.2M25.20 mi0.35 mi20676+2512476+1612476+1618887(Top 71%)11422(Top 75%)11422(Top 557%)
Finish26.22 mi1.02 mi20588+8812431+4512431+4518111(Top 68%)11140(Top 73%)11140(Top 543%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 79%
×21stories
+97ft-345ft

Overall

21106

Males

12793

M50-54

12793

5K→10K

3.1 - 6.2 mi

Top 78%
×5stories
+79ft-138ft

Overall

20857

Males

12649

M50-54

12649

10K→15K

6.2 - 9.3 mi

Top 79%
×3stories
+67ft-78ft

Overall

21106

Males

12793

M50-54

12793

15K→20K

9.3 - 12.4 mi

Top 78%
×5stories
+106ft-86ft

Overall

20739

Males

12636

M50-54

12636

20K→Half

12.4 - 13.1 mi

Top 82%
×2stories
+19ft-37ft

Overall

21738

Males

13059

M50-54

13059

Half→25K

13.1 - 15.5 mi

Top 80%
×4stories
+66ft-88ft

Overall

21218

Males

12802

M50-54

12802

25K→30K

15.5 - 18.6 mi

Top 79%
×9stories
+181ft-148ft

Overall

21095

Males

12675

M50-54

12675

30K→20M

18.6 - 20.0 mi

Top 79%
×5stories
+64ft-50ft

Overall

21052

Males

12591

M50-54

12591

20M→21M

20.0 - 21.0 mi

Top 73%
×8stories
+106ft-24ft

Overall

19428

Males

11810

M50-54

11810

21M→35K

21.0 - 21.8 mi

Top 80%
×7stories
+17ft-86ft

Overall

21187

Males

12569

M50-54

12569

35K→23M

21.8 - 23.0 mi

Top 75%
×5stories
+23ft-63ft

Overall

20051

Males

12044

M50-54

12044

23M→24M

23.0 - 24.0 mi

Top 75%
×6stories
+12ft-82ft

Overall

19947

Males

11981

M50-54

11981

24M→40K

24.0 - 24.9 mi

Top 74%
×1story
+6ft-20ft

Overall

19748

Males

11808

M50-54

11808

40K→25.2M

24.9 - 25.2 mi

Top 71%
×1story
+13ft-16ft

Overall

18887

Males

11422

M50-54

11422

25.2M→Finish

25.2 - 26.2 mi

Top 68%
×2stories
+22ft-21ft

Overall

18111

Males

11140

M50-54

11140

Passing Analysis

Category:
Athletes Passed
1395
Passed By
1308
Net Change
+87
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#20675
5K → 10K273335-62#20675#20737
10K → 15K125248-123#20737#20860
15K → 20K181137+44#20860#20816
20K → Half1775-58#20816#20874
Half → 25K78139-61#20874#20935
25K → 30K135163-28#20935#20963
30K → 20M7865+13#20963#20950
20M → 21M11517+98#20950#20852
21M → 35K3239-7#20852#20859
35K → 23M10541+64#20859#20795
23M → 24M6217+45#20795#20750
24M → 40K6617+49#20750#20701
40K → 25.2M316+25#20701#20676
25.2M → Finish979+88#20676#20588
TOTALS13951308+87
📊

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