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BOSTON MARATHON 2023

Mark Retzlaff

Bib: 8755•M

OR

0:00
0:00
/ mi
Masters
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Overall
#0 / 26622
Top 25%
Gender (Male)
#0 / 15176
Top 38%
Masters (Masters Men)
#0 / 9891
Top 24%
Division (M40-44)
#0 / 2241
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
21:07
Rank: #4655
Start → 5K
21:07 | 6:48/mi
10K· 6.21 mi
42:31
Rank: #5342 (-687)
5K → 10K
21:24 | 6:53/mi
15K· 9.32 mi
1:04:00
Rank: #5601 (-259)
10K → 15K
21:29 | 6:55/mi
20K· 12.43 mi
1:25:41
Rank: #5676 (-75)
15K → 20K
21:41 | 6:59/mi
Half· 13.11 mi
1:30:24
Rank: #5693 (-17)
20K → Half
4:43 | 6:55/mi
25K· 15.53 mi
1:47:18
Rank: #5638 (+55)
Half → 25K
16:54 | 6:58/mi
30K· 18.64 mi
2:10:29
Rank: #5814 (-176)
25K → 30K
23:11 | 7:28/mi
20M
2:20:23
Rank: #5763 (+51)
30K → 20M
9:54 | 7:17/mi
21M
2:28:24
Rank: #5801 (-38)
20M → 21M
8:01 | 8:01/mi
35K· 21.75 mi
2:33:52
Rank: #5825 (-24)
21M → 35K
5:28 | 7:18/mi
23M
2:43:37
Rank: #5888 (-63)
35K → 23M
9:45 | 7:47/mi
24M
2:51:39
Rank: #6042 (-154)
23M → 24M
8:02 | 8:02/mi
40K· 24.85 mi
2:58:54
Rank: #6222 (-180)
24M → 40K
7:15 | 8:29/mi
25.2M
3:02:08
Rank: #6327 (-105)
40K → 25.2M
3:14 | 9:23/mi
Finish· 26.22 mi
3:10:33
Rank: #6540 (-213)
25.2M → Finish
8:25 | 8:16/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:30:24
Pace6:54 /mi
2nd Half
Distance13.11 mi
Time1:40:09
Pace7:38 /mi
📊Positive Split: 10.8% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:46:1621:076:4821:07
6:48
-
10K
6.21 mi11:07:4042:316:5121:24
6:53
+0:05
15K
9.32 mi11:29:091:04:006:5221:29
6:55
+0:02
20K
12.43 mi11:50:501:25:416:5421:41
6:59
+0:04
Half
13.11 mi11:55:331:30:246:544:43
6:55
-0:04
25K
15.53 mi12:12:271:47:186:5416:54
6:58
+0:03
30K
18.64 mi12:35:382:10:297:0023:11
7:28
+0:30
20M
20.00 mi12:45:322:20:237:019:54
7:17
-0:11
21M
21.00 mi12:53:332:28:247:048:01
8:01
+0:44
35K
21.75 mi12:59:012:33:527:045:28
7:18
-0:43
23M
23.00 mi13:08:462:43:377:079:45
7:47
+0:29
24M
24.00 mi13:16:482:51:397:098:02
8:02
+0:15
40K
24.85 mi13:24:032:58:547:127:15
8:29
+0:27
25.2M
25.20 mi13:27:173:02:087:143:14
9:23
+0:54
Finish
26.22 mi13:35:423:10:337:168:25
8:16
-1:07

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

6:48 /mi

Average Pace

7:16 /mi

Slowest Pace

9:23 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

1:08:43

36% of race

Time at Steady Pace

1:17:08

40% of race

Time at Slower Pace

44:42

23% of race

Average Pace: 7:16 /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 mi10:46:1621:076:4821:07
6:48
#4655
10K
6.21 mi11:07:4042:316:5121:24
6:53
#5342
15K
9.32 mi11:29:091:04:006:5221:29
6:55
#5601
20K
12.43 mi11:50:501:25:416:5421:41
6:59
#5676
Half
13.11 mi11:55:331:30:246:544:43
6:55
#5693
25K
15.53 mi12:12:271:47:186:5416:54
6:58
#5638
30K
18.64 mi12:35:382:10:297:0023:11
7:28
#5814
20M
20.00 mi12:45:322:20:237:019:54
7:17
#5763
21M
21.00 mi12:53:332:28:247:048:01
8:01
#5801
35K
21.75 mi12:59:012:33:527:045:28
7:18
#5825
23M
23.00 mi13:08:462:43:377:079:45
7:47
#5888
24M
24.00 mi13:16:482:51:397:098:02
8:02
#6042
40K
24.85 mi13:24:032:58:547:127:15
8:29
#6222
25.2M
25.20 mi13:27:173:02:087:143:14
9:23
#6327
Finish
26.22 mi13:35:423:10:337:168:25
8:16
#6540
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM40-44Seg. OverallSeg. MalesSeg. M40-44
5K3.11 mi3.11 mi4655433843386061(Top 23%)5507(Top 36%)5507(Top 246%)
10K6.21 mi3.10 mi5342-6874937-5994937-5996039(Top 23%)5494(Top 36%)5494(Top 245%)
15K9.32 mi3.11 mi5601-2595156-2195156-2196061(Top 23%)5507(Top 36%)5507(Top 246%)
20K12.43 mi3.11 mi5676-755226-705226-705868(Top 22%)5366(Top 35%)5366(Top 239%)
Half13.11 mi0.68 mi5693-175242-165242-166076(Top 23%)5546(Top 37%)5546(Top 247%)
25K15.53 mi2.42 mi5638+555188+545188+545419(Top 20%)4994(Top 33%)4994(Top 223%)
30K18.64 mi3.11 mi5814-1765323-1355323-1356963(Top 26%)6037(Top 40%)6037(Top 269%)
20M20.00 mi1.36 mi5763+515271+525271+525564(Top 21%)4976(Top 33%)4976(Top 222%)
21M21.00 mi1.00 mi5801-385292-215292-217422(Top 28%)6126(Top 40%)6126(Top 273%)
35K21.75 mi0.75 mi5825-245302-105302-107138(Top 27%)5978(Top 39%)5978(Top 267%)
23M23.00 mi1.25 mi5888-635338-365338-368294(Top 31%)6569(Top 43%)6569(Top 293%)
24M24.00 mi1.00 mi6042-1545439-1015439-10111422(Top 43%)8098(Top 53%)8098(Top 361%)
40K24.85 mi0.85 mi6222-1805569-1305569-13013149(Top 49%)8834(Top 58%)8834(Top 394%)
25.2M25.20 mi0.35 mi6327-1055644-755644-7514470(Top 54%)9426(Top 62%)9426(Top 421%)
Finish26.22 mi1.02 mi6540-2135775-1315775-13113791(Top 52%)9132(Top 60%)9132(Top 407%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 23%
×21stories
+97ft-345ft

Overall

6061

Males

5507

M40-44

5507

5K→10K

3.1 - 6.2 mi

Top 23%
×5stories
+79ft-138ft

Overall

6039

Males

5494

M40-44

5494

10K→15K

6.2 - 9.3 mi

Top 23%
×3stories
+67ft-78ft

Overall

6061

Males

5507

M40-44

5507

15K→20K

9.3 - 12.4 mi

Top 22%
×5stories
+106ft-86ft

Overall

5868

Males

5366

M40-44

5366

20K→Half

12.4 - 13.1 mi

Top 23%
×2stories
+19ft-37ft

Overall

6076

Males

5546

M40-44

5546

Half→25K

13.1 - 15.5 mi

Top 20%
×4stories
+66ft-88ft

Overall

5419

Males

4994

M40-44

4994

25K→30K

15.5 - 18.6 mi

Top 26%
×9stories
+181ft-148ft

Overall

6963

Males

6037

M40-44

6037

30K→20M

18.6 - 20.0 mi

Top 21%
×5stories
+64ft-50ft

Overall

5564

Males

4976

M40-44

4976

20M→21M

20.0 - 21.0 mi

Top 28%
×8stories
+106ft-24ft

Overall

7422

Males

6126

M40-44

6126

21M→35K

21.0 - 21.8 mi

Top 27%
×7stories
+17ft-86ft

Overall

7138

Males

5978

M40-44

5978

35K→23M

21.8 - 23.0 mi

Top 31%
×5stories
+23ft-63ft

Overall

8294

Males

6569

M40-44

6569

23M→24M

23.0 - 24.0 mi

Top 43%
×6stories
+12ft-82ft

Overall

11422

Males

8098

M40-44

8098

24M→40K

24.0 - 24.9 mi

Top 49%
×1story
+6ft-20ft

Overall

13149

Males

8834

M40-44

8834

40K→25.2M

24.9 - 25.2 mi

Top 54%
×1story
+13ft-16ft

Overall

14470

Males

9426

M40-44

9426

25.2M→Finish

25.2 - 26.2 mi

Top 52%
×2stories
+22ft-21ft

Overall

13791

Males

9132

M40-44

9132

Passing Analysis

Category:
Athletes Passed
612
Passed By
2497
Net Change
-1885
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#4655
5K → 10K44731-687#4655#5342
10K → 15K44303-259#5342#5601
15K → 20K82157-75#5601#5676
20K → Half825-17#5676#5693
Half → 25K10449+55#5693#5638
25K → 30K73249-176#5638#5814
30K → 20M8736+51#5814#5763
20M → 21M4785-38#5763#5801
21M → 35K2347-24#5801#5825
35K → 23M39102-63#5825#5888
23M → 24M29183-154#5888#6042
24M → 40K16196-180#6042#6222
40K → 25.2M5110-105#6222#6327
25.2M → Finish11224-213#6327#6540
TOTALS6122497-1885
📊

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