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BOSTON MARATHON 2023

Zac Zarling

Bib: 11543•M

IL

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Top 23%
Gender (Male)
#0 / 15176
Top 36%
Masters (Masters Men)
#0 / 9891
Top 22%
Division (M45-49)
#0 / 2252
Top 28%
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
23:34
Rank: #10374
Start → 5K
23:34 | 7:35/mi
10K· 6.21 mi
46:31
Rank: #9881 (+493)
5K → 10K
22:57 | 7:23/mi
15K· 9.32 mi
1:08:52
Rank: #9096 (+785)
10K → 15K
22:21 | 7:12/mi
20K· 12.43 mi
1:31:03
Rank: #8430 (+666)
15K → 20K
22:11 | 7:08/mi
Half· 13.11 mi
1:35:49
Rank: #8319 (+111)
20K → Half
4:46 | 6:59/mi
25K· 15.53 mi
1:52:59
Rank: #7878 (+441)
Half → 25K
17:10 | 7:05/mi
30K· 18.64 mi
2:15:18
Rank: #7344 (+534)
25K → 30K
22:19 | 7:11/mi
20M
2:25:05
Rank: #7144 (+200)
30K → 20M
9:47 | 7:12/mi
21M
2:32:40
Rank: #6976 (+168)
20M → 21M
7:35 | 7:35/mi
35K· 21.75 mi
2:37:51
Rank: #6887 (+89)
21M → 35K
5:11 | 6:56/mi
23M
2:46:44
Rank: #6690 (+197)
35K → 23M
8:53 | 7:06/mi
24M
2:53:31
Rank: #6515 (+175)
23M → 24M
6:47 | 6:47/mi
40K· 24.85 mi
2:59:24
Rank: #6342 (+173)
24M → 40K
5:53 | 6:53/mi
25.2M
3:01:53
Rank: #6257 (+85)
40K → 25.2M
2:29 | 7:12/mi
Finish· 26.22 mi
3:08:46
Rank: #6126 (+131)
25.2M → Finish
6:53 | 6:45/mi

The Course

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Half Splits

1st Half· via Half
Distance13.11 mi
Time1:35:49
Pace7:19 /mi
2nd Half✓ Faster
Distance13.11 mi
Time1:32:57
Pace7:05 /mi
📊Negative Split: 3.0% faster second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:50:2523:347:3523:34
7:35
-
10K
6.21 mi11:13:2246:317:2922:57
7:23
-0:12
15K
9.32 mi11:35:431:08:527:2322:21
7:12
-0:11
20K
12.43 mi11:57:541:31:037:2022:11
7:08
-0:04
Half
13.11 mi12:02:401:35:497:194:46
6:59
-0:09
25K
15.53 mi12:19:501:52:597:1617:10
7:05
+0:06
30K
18.64 mi12:42:092:15:187:1522:19
7:11
+0:06
20M
20.00 mi12:51:562:25:057:159:47
7:12
+0:01
21M
21.00 mi12:59:312:32:407:167:35
7:35
+0:23
35K
21.75 mi13:04:422:37:517:155:11
6:56
-0:39
23M
23.00 mi13:13:352:46:447:158:53
7:06
+0:10
24M
24.00 mi13:20:222:53:317:146:47
6:47
-0:19
40K
24.85 mi13:26:152:59:247:135:53
6:53
+0:06
25.2M
25.20 mi13:28:443:01:537:132:29
7:12
+0:19
Finish
26.22 mi13:35:373:08:467:126:53
6:45
-0:27

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

6:45 /mi

Average Pace

7:12 /mi

Slowest Pace

7:35 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

2:37:37

83% of race

Time at Steady Pace

31:09

17% of race

Time at Slower Pace

0:00

0% of race

Average Pace: 7:12 /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 mi10:50:2523:347:3523:34
7:35
#10374
10K
6.21 mi11:13:2246:317:2922:57
7:23
#9881
15K
9.32 mi11:35:431:08:527:2322:21
7:12
#9096
20K
12.43 mi11:57:541:31:037:2022:11
7:08
#8430
Half
13.11 mi12:02:401:35:497:194:46
6:59
#8319
25K
15.53 mi12:19:501:52:597:1617:10
7:05
#7878
30K
18.64 mi12:42:092:15:187:1522:19
7:11
#7344
20M
20.00 mi12:51:562:25:057:159:47
7:12
#7144
21M
21.00 mi12:59:312:32:407:167:35
7:35
#6976
35K
21.75 mi13:04:422:37:517:155:11
6:56
#6887
23M
23.00 mi13:13:352:46:447:158:53
7:06
#6690
24M
24.00 mi13:20:222:53:317:146:47
6:47
#6515
40K
24.85 mi13:26:152:59:247:135:53
6:53
#6342
25.2M
25.20 mi13:28:443:01:537:132:29
7:12
#6257
Finish
26.22 mi13:35:373:08:467:126:53
6:45
#6126
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM45-49Seg. OverallSeg. MalesSeg. M45-49
5K3.11 mi3.11 mi10374833383337753(Top 29%)6753(Top 44%)6753(Top 300%)
10K6.21 mi3.10 mi9881+4938082+2518082+2519470(Top 36%)7842(Top 52%)7842(Top 348%)
15K9.32 mi3.11 mi9096+7857616+4667616+4667753(Top 29%)6753(Top 44%)6753(Top 300%)
20K12.43 mi3.11 mi8430+6667208+4087208+4086753(Top 25%)6028(Top 40%)6028(Top 268%)
Half13.11 mi0.68 mi8319+1117141+677141+676444(Top 24%)5820(Top 38%)5820(Top 258%)
25K15.53 mi2.42 mi7878+4416833+3086833+3086016(Top 23%)5455(Top 36%)5455(Top 242%)
30K18.64 mi3.11 mi7344+5346460+3736460+3735399(Top 20%)4921(Top 32%)4921(Top 219%)
20M20.00 mi1.36 mi7144+2006309+1516309+1515114(Top 19%)4636(Top 31%)4636(Top 206%)
21M21.00 mi1.00 mi6976+1686175+1346175+1345009(Top 19%)4487(Top 30%)4487(Top 199%)
35K21.75 mi0.75 mi6887+896098+776098+774957(Top 19%)4463(Top 29%)4463(Top 198%)
23M23.00 mi1.25 mi6690+1975936+1625936+1624297(Top 16%)3924(Top 26%)3924(Top 174%)
24M24.00 mi1.00 mi6515+1755794+1425794+1423582(Top 13%)3293(Top 22%)3293(Top 146%)
40K24.85 mi0.85 mi6342+1735658+1365658+1363257(Top 12%)2987(Top 20%)2987(Top 133%)
25.2M25.20 mi0.35 mi6257+855586+725586+722588(Top 10%)2401(Top 16%)2401(Top 107%)
Finish26.22 mi1.02 mi6126+1315472+1145472+1143826(Top 14%)3398(Top 22%)3398(Top 151%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 29%
×21stories
+97ft-345ft

Overall

7753

Males

6753

M45-49

6753

5K→10K

3.1 - 6.2 mi

Top 36%
×5stories
+79ft-138ft

Overall

9470

Males

7842

M45-49

7842

10K→15K

6.2 - 9.3 mi

Top 29%
×3stories
+67ft-78ft

Overall

7753

Males

6753

M45-49

6753

15K→20K

9.3 - 12.4 mi

Top 25%
×5stories
+106ft-86ft

Overall

6753

Males

6028

M45-49

6028

20K→Half

12.4 - 13.1 mi

Top 24%
×2stories
+19ft-37ft

Overall

6444

Males

5820

M45-49

5820

Half→25K

13.1 - 15.5 mi

Top 23%
×4stories
+66ft-88ft

Overall

6016

Males

5455

M45-49

5455

25K→30K

15.5 - 18.6 mi

Top 20%
×9stories
+181ft-148ft

Overall

5399

Males

4921

M45-49

4921

30K→20M

18.6 - 20.0 mi

Top 19%
×5stories
+64ft-50ft

Overall

5114

Males

4636

M45-49

4636

20M→21M

20.0 - 21.0 mi

Top 19%
×8stories
+106ft-24ft

Overall

5009

Males

4487

M45-49

4487

21M→35K

21.0 - 21.8 mi

Top 19%
×7stories
+17ft-86ft

Overall

4957

Males

4463

M45-49

4463

35K→23M

21.8 - 23.0 mi

Top 16%
×5stories
+23ft-63ft

Overall

4297

Males

3924

M45-49

3924

23M→24M

23.0 - 24.0 mi

Top 13%
×6stories
+12ft-82ft

Overall

3582

Males

3293

M45-49

3293

24M→40K

24.0 - 24.9 mi

Top 12%
×1story
+6ft-20ft

Overall

3257

Males

2987

M45-49

2987

40K→25.2M

24.9 - 25.2 mi

Top 10%
×1story
+13ft-16ft

Overall

2588

Males

2401

M45-49

2401

25.2M→Finish

25.2 - 26.2 mi

Top 14%
×2stories
+22ft-21ft

Overall

3826

Males

3398

M45-49

3398

Passing Analysis

Category:
Athletes Passed
4411*
Passed By
163
Net Change
+4248
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#10374
5K → 10K613*120+493#10374#9881
10K → 15K7938+785#9881#9096
15K → 20K6693+666#9096#8430
20K → Half1110+111#8430#8319
Half → 25K4421+441#8319#7878
25K → 30K5373+534#7878#7344
30K → 20M2022+200#7344#7144
20M → 21M1768+168#7144#6976
21M → 35K945+89#6976#6887
35K → 23M1981+197#6887#6690
23M → 24M1761+175#6690#6515
24M → 40K1741+173#6515#6342
40K → 25.2M850+85#6342#6257
25.2M → Finish14110+131#6257#6126
TOTALS4411*163+4248

* 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