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BOSTON MARATHON 2023

David Zlotlow

Bib: 8605•M

CA

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Top 36%
Gender (Male)
#0 / 15176
Masters (Masters Men)
#0 / 9891
Top 40%
Division (M45-49)
#0 / 2252
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
24:33
Rank: #13232
Start → 5K
24:33 | 7:54/mi
10K· 6.21 mi
49:02
Rank: #13509 (-277)
5K → 10K
24:29 | 7:53/mi
15K· 9.32 mi
1:12:39
Rank: #12627 (+882)
10K → 15K
23:37 | 7:36/mi
20K· 12.43 mi
1:36:42
Rank: #12219 (+408)
15K → 20K
24:03 | 7:44/mi
Half· 13.11 mi
1:41:59
Rank: #12224 (-5)
20K → Half
5:17 | 7:45/mi
25K· 15.53 mi
2:00:49
Rank: #11980 (+244)
Half → 25K
18:50 | 7:46/mi
30K· 18.64 mi
2:25:05
Rank: #11465 (+515)
25K → 30K
24:16 | 7:49/mi
20M
2:35:38
Rank: #11196 (+269)
30K → 20M
10:33 | 7:46/mi
21M
2:43:24
Rank: #10855 (+341)
20M → 21M
7:46 | 7:46/mi
35K· 21.75 mi
2:48:45
Rank: #10643 (+212)
21M → 35K
5:21 | 7:09/mi
23M
2:58:01
Rank: #10322 (+321)
35K → 23M
9:16 | 7:24/mi
24M
3:05:21
Rank: #10126 (+196)
23M → 24M
7:20 | 7:20/mi
40K· 24.85 mi
3:11:41
Rank: #9931 (+195)
24M → 40K
6:20 | 7:24/mi
25.2M
3:14:28
Rank: #9863 (+68)
40K → 25.2M
2:47 | 8:04/mi
Finish· 26.22 mi
3:21:43
Rank: #9650 (+213)
25.2M → Finish
7:15 | 7:07/mi

The Course

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Half Splits

1st Half· via Half
Distance13.11 mi
Time1:41:59
Pace7:47 /mi
2nd Half✓ Faster
Distance13.11 mi
Time1:39:44
Pace7:36 /mi
📊Negative Split: 2.2% faster second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:49:5924:337:5424:33
7:54
-
10K
6.21 mi11:14:2849:027:5324:29
7:53
-0:01
15K
9.32 mi11:38:051:12:397:4823:37
7:36
-0:17
20K
12.43 mi12:02:081:36:427:4724:03
7:44
+0:08
Half
13.11 mi12:07:251:41:597:475:17
7:45
+0:01
25K
15.53 mi12:26:152:00:497:4718:50
7:46
+0:01
30K
18.64 mi12:50:312:25:057:4724:16
7:49
+0:03
20M
20.00 mi13:01:042:35:387:4710:33
7:46
-0:03
21M
21.00 mi13:08:502:43:247:477:46
7:46
0:00
35K
21.75 mi13:14:112:48:457:465:21
7:09
-0:37
23M
23.00 mi13:23:272:58:017:449:16
7:24
+0:15
24M
24.00 mi13:30:473:05:217:437:20
7:20
-0:04
40K
24.85 mi13:37:073:11:417:436:20
7:24
+0:04
25.2M
25.20 mi13:39:543:14:287:432:47
8:04
+0:40
Finish
26.22 mi13:47:093:21:437:427:15
7:07
-0:57

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

7:07 /mi

Average Pace

7:42 /mi

Slowest Pace

8:04 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:29:54

74% of race

Time at Steady Pace

51:49

26% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 7:42 /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 mi10:49:5924:337:5424:33
7:54
#13232
10K
6.21 mi11:14:2849:027:5324:29
7:53
#13509
15K
9.32 mi11:38:051:12:397:4823:37
7:36
#12627
20K
12.43 mi12:02:081:36:427:4724:03
7:44
#12219
Half
13.11 mi12:07:251:41:597:475:17
7:45
#12224
25K
15.53 mi12:26:152:00:497:4718:50
7:46
#11980
30K
18.64 mi12:50:312:25:057:4724:16
7:49
#11465
20M
20.00 mi13:01:042:35:387:4710:33
7:46
#11196
21M
21.00 mi13:08:502:43:247:477:46
7:46
#10855
35K
21.75 mi13:14:112:48:457:465:21
7:09
#10643
23M
23.00 mi13:23:272:58:017:449:16
7:24
#10322
24M
24.00 mi13:30:473:05:217:437:20
7:20
#10126
40K
24.85 mi13:37:073:11:417:436:20
7:24
#9931
25.2M
25.20 mi13:39:543:14:287:432:47
8:04
#9863
Finish
26.22 mi13:47:093:21:437:427:15
7:07
#9650
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM45-49Seg. OverallSeg. MalesSeg. M45-49
5K3.11 mi3.11 mi132329638963811014(Top 41%)8643(Top 57%)8643(Top 384%)
10K6.21 mi3.10 mi13509-2779746-1089746-10813795(Top 52%)9853(Top 65%)9853(Top 438%)
15K9.32 mi3.11 mi12627+8829360+3869360+38611014(Top 41%)8643(Top 57%)8643(Top 384%)
20K12.43 mi3.11 mi12219+4089158+2029158+20211220(Top 42%)8676(Top 57%)8676(Top 385%)
Half13.11 mi0.68 mi12224-59156+29156+212159(Top 46%)9113(Top 60%)9113(Top 405%)
25K15.53 mi2.42 mi11980+2449036+1209036+12010822(Top 41%)8402(Top 55%)8402(Top 373%)
30K18.64 mi3.11 mi11465+5158775+2618775+2619438(Top 35%)7524(Top 50%)7524(Top 334%)
20M20.00 mi1.36 mi11196+2698635+1408635+1408580(Top 32%)6947(Top 46%)6947(Top 308%)
21M21.00 mi1.00 mi10855+3418451+1848451+1846012(Top 23%)5210(Top 34%)5210(Top 231%)
35K21.75 mi0.75 mi10643+2128332+1198332+1196238(Top 23%)5410(Top 36%)5410(Top 240%)
23M23.00 mi1.25 mi10322+3218149+1838149+1835881(Top 22%)5106(Top 34%)5106(Top 227%)
24M24.00 mi1.00 mi10126+1968025+1248025+1246615(Top 25%)5505(Top 36%)5505(Top 244%)
40K24.85 mi0.85 mi9931+1957886+1397886+1396145(Top 23%)5119(Top 34%)5119(Top 227%)
25.2M25.20 mi0.35 mi9863+687841+457841+456910(Top 26%)5542(Top 37%)5542(Top 246%)
Finish26.22 mi1.02 mi9650+2137699+1427699+1425909(Top 22%)4875(Top 32%)4875(Top 216%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 41%
×21stories
+97ft-345ft

Overall

11014

Males

8643

M45-49

8643

5K→10K

3.1 - 6.2 mi

Top 52%
×5stories
+79ft-138ft

Overall

13795

Males

9853

M45-49

9853

10K→15K

6.2 - 9.3 mi

Top 41%
×3stories
+67ft-78ft

Overall

11014

Males

8643

M45-49

8643

15K→20K

9.3 - 12.4 mi

Top 42%
×5stories
+106ft-86ft

Overall

11220

Males

8676

M45-49

8676

20K→Half

12.4 - 13.1 mi

Top 46%
×2stories
+19ft-37ft

Overall

12159

Males

9113

M45-49

9113

Half→25K

13.1 - 15.5 mi

Top 41%
×4stories
+66ft-88ft

Overall

10822

Males

8402

M45-49

8402

25K→30K

15.5 - 18.6 mi

Top 35%
×9stories
+181ft-148ft

Overall

9438

Males

7524

M45-49

7524

30K→20M

18.6 - 20.0 mi

Top 32%
×5stories
+64ft-50ft

Overall

8580

Males

6947

M45-49

6947

20M→21M

20.0 - 21.0 mi

Top 23%
×8stories
+106ft-24ft

Overall

6012

Males

5210

M45-49

5210

21M→35K

21.0 - 21.8 mi

Top 23%
×7stories
+17ft-86ft

Overall

6238

Males

5410

M45-49

5410

35K→23M

21.8 - 23.0 mi

Top 22%
×5stories
+23ft-63ft

Overall

5881

Males

5106

M45-49

5106

23M→24M

23.0 - 24.0 mi

Top 25%
×6stories
+12ft-82ft

Overall

6615

Males

5505

M45-49

5505

24M→40K

24.0 - 24.9 mi

Top 23%
×1story
+6ft-20ft

Overall

6145

Males

5119

M45-49

5119

40K→25.2M

24.9 - 25.2 mi

Top 26%
×1story
+13ft-16ft

Overall

6910

Males

5542

M45-49

5542

25.2M→Finish

25.2 - 26.2 mi

Top 22%
×2stories
+22ft-21ft

Overall

5909

Males

4875

M45-49

4875

Passing Analysis

Category:
Athletes Passed
4189*
Passed By
607
Net Change
+3582
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#13232
5K → 10K187464-277#13232#13509
10K → 15K89816+882#13509#12627
15K → 20K43527+408#12627#12219
20K → Half2934-5#12219#12224
Half → 25K26925+244#12224#11980
25K → 30K53015+515#11980#11465
30K → 20M2745+269#11465#11196
20M → 21M3410+341#11196#10855
21M → 35K2120+212#10855#10643
35K → 23M3232+321#10643#10322
23M → 24M2026+196#10322#10126
24M → 40K198*3+195#10126#9931
40K → 25.2M735+68#9931#9863
25.2M → Finish218*5+213#9863#9650
TOTALS4189*607+3582

* Includes athletes who did not complete a segment (DNF/DNQ).

📊

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