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BOSTON MARATHON 2023

Nathan Loersch

Bib: 3905•M

SC

0:00
0:00
/ mi
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Overall
#0 / 26622
Top 30%
Gender (Male)
#0 / 15176
Top 44%
Division (M18-39)
#0 / 5285
Race Day Weather
49°/39°F
light intensity drizzle

⏱️ Race Timeline

Start
0:00:00
Race begins
5K· 3.11 mi
22:03
Rank: #6866
Start → 5K
22:03 | 7:06/mi
10K· 6.21 mi
43:42
Rank: #6693 (+173)
5K → 10K
21:39 | 6:58/mi
15K· 9.32 mi
1:06:18
Rank: #7181 (-488)
10K → 15K
22:36 | 7:16/mi
20K· 12.43 mi
1:28:59
Rank: #7276 (-95)
15K → 20K
22:41 | 7:18/mi
Half· 13.11 mi
1:33:46
Rank: #7249 (+27)
20K → Half
4:47 | 7:01/mi
25K· 15.53 mi
1:51:20
Rank: #7173 (+76)
Half → 25K
17:34 | 7:15/mi
30K· 18.64 mi
2:15:55
Rank: #7581 (-408)
25K → 30K
24:35 | 7:55/mi
20M
2:26:07
Rank: #7475 (+106)
30K → 20M
10:12 | 7:30/mi
21M
2:33:58
Rank: #7402 (+73)
20M → 21M
7:51 | 7:51/mi
35K· 21.75 mi
2:39:26
Rank: #7380 (+22)
21M → 35K
5:28 | 7:18/mi
23M
2:49:07
Rank: #7365 (+15)
35K → 23M
9:41 | 7:44/mi
24M
2:56:46
Rank: #7374 (-9)
23M → 24M
7:39 | 7:39/mi
40K· 24.85 mi
3:04:42
Rank: #7788 (-414)
24M → 40K
7:56 | 9:17/mi
25.2M
3:08:23
Rank: #8019 (-231)
40K → 25.2M
3:41 | 10:41/mi
Finish· 26.22 mi
3:16:00
Rank: #8017 (+2)
25.2M → Finish
7:37 | 7:28/mi

The Course

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Half Splits

1st Half· via HalfFaster
Distance13.11 mi
Time1:33:46
Pace7:09 /mi
2nd Half
Distance13.11 mi
Time1:42:14
Pace7:48 /mi
📊Positive Split: 9.0% slower second half

Checkpoint Splits

CheckpointDistanceTime of DayTimeAvg PaceSegment TimeSegment PaceDiff
5K
3.11 mi10:23:3322:037:0622:03
7:06
-
10K
6.21 mi10:45:1243:427:0221:39
6:58
-0:08
15K
9.32 mi11:07:481:06:187:0722:36
7:16
+0:18
20K
12.43 mi11:30:291:28:597:1022:41
7:18
+0:02
Half
13.11 mi11:35:161:33:467:094:47
7:01
-0:17
25K
15.53 mi11:52:501:51:207:1017:34
7:15
+0:14
30K
18.64 mi12:17:252:15:557:1724:35
7:55
+0:40
20M
20.00 mi12:27:372:26:077:1810:12
7:30
-0:25
21M
21.00 mi12:35:282:33:587:207:51
7:51
+0:21
35K
21.75 mi12:40:562:39:267:205:28
7:18
-0:33
23M
23.00 mi12:50:372:49:077:219:41
7:44
+0:26
24M
24.00 mi12:58:162:56:467:227:39
7:39
-0:05
40K
24.85 mi13:06:123:04:427:267:56
9:17
+1:38
25.2M
25.20 mi13:09:533:08:237:293:41
10:41
+1:24
Finish
26.22 mi13:17:303:16:007:297:37
7:28
-3:13

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

6:58 /mi

Average Pace

7:29 /mi

Slowest Pace

10:41 /mi

Loading chart...
Fastest
Middle
Slowest
Average

📊Segments

Segment Time Comparison

Time at Faster Pace

21:39

11% of race

Time at Steady Pace

2:42:44

83% of race

Time at Slower Pace

11:37

6% of race

Average Pace: 7:29 /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 mi10:23:3322:037:0622:03
7:06
#6866
10K
6.21 mi10:45:1243:427:0221:39
6:58
#6693
15K
9.32 mi11:07:481:06:187:0722:36
7:16
#7181
20K
12.43 mi11:30:291:28:597:1022:41
7:18
#7276
Half
13.11 mi11:35:161:33:467:094:47
7:01
#7249
25K
15.53 mi11:52:501:51:207:1017:34
7:15
#7173
30K
18.64 mi12:17:252:15:557:1724:35
7:55
#7581
20M
20.00 mi12:27:372:26:077:1810:12
7:30
#7475
21M
21.00 mi12:35:282:33:587:207:51
7:51
#7402
35K
21.75 mi12:40:562:39:267:205:28
7:18
#7380
23M
23.00 mi12:50:372:49:077:219:41
7:44
#7365
24M
24.00 mi12:58:162:56:467:227:39
7:39
#7374
40K
24.85 mi13:06:123:04:427:267:56
9:17
#7788
25.2M
25.20 mi13:09:533:08:237:293:41
10:41
#8019
Finish
26.22 mi13:17:303:16:007:297:37
7:28
#8017
Faster pace
Steady pace
Slower pace

Checkpoint and Segment Rankings

CheckpointDistanceSeg. DistOverallMalesM18-39Seg. OverallSeg. MalesSeg. M18-39
5K3.11 mi3.11 mi6866617661768342(Top 31%)7135(Top 47%)7135(Top 135%)
10K6.21 mi3.10 mi6693+1736029+1476029+1476608(Top 25%)5940(Top 39%)5940(Top 112%)
15K9.32 mi3.11 mi7181-4886386-3576386-3578342(Top 31%)7135(Top 47%)7135(Top 135%)
20K12.43 mi3.11 mi7276-956448-626448-627788(Top 29%)6751(Top 44%)6751(Top 128%)
Half13.11 mi0.68 mi7249+276429+196429+196615(Top 25%)5955(Top 39%)5955(Top 113%)
25K15.53 mi2.42 mi7173+766363+666363+666928(Top 26%)6107(Top 40%)6107(Top 116%)
30K18.64 mi3.11 mi7581-4086614-2516614-25110214(Top 38%)7935(Top 52%)7935(Top 150%)
20M20.00 mi1.36 mi7475+1066520+946520+946825(Top 26%)5865(Top 39%)5865(Top 111%)
21M21.00 mi1.00 mi7402+736448+726448+726449(Top 24%)5521(Top 36%)5521(Top 104%)
35K21.75 mi0.75 mi7380+226429+196429+197163(Top 27%)6003(Top 40%)6003(Top 114%)
23M23.00 mi1.25 mi7365+156393+366393+367944(Top 30%)6379(Top 42%)6379(Top 121%)
24M24.00 mi1.00 mi7374-96386+76386+78714(Top 33%)6732(Top 44%)6732(Top 127%)
40K24.85 mi0.85 mi7788-4146633-2476633-24717394(Top 65%)10743(Top 71%)10743(Top 203%)
25.2M25.20 mi0.35 mi8019-2316767-1346767-13419594(Top 74%)11718(Top 77%)11718(Top 222%)
Finish26.22 mi1.02 mi8017+26746+216746+218349(Top 31%)6365(Top 42%)6365(Top 120%)

Segment Performance Analysis

10K→15K

0.0 - 3.1 mi

Top 31%
×21stories
+97ft-345ft

Overall

8342

Males

7135

M18-39

7135

5K→10K

3.1 - 6.2 mi

Top 25%
×5stories
+79ft-138ft

Overall

6608

Males

5940

M18-39

5940

10K→15K

6.2 - 9.3 mi

Top 31%
×3stories
+67ft-78ft

Overall

8342

Males

7135

M18-39

7135

15K→20K

9.3 - 12.4 mi

Top 29%
×5stories
+106ft-86ft

Overall

7788

Males

6751

M18-39

6751

20K→Half

12.4 - 13.1 mi

Top 25%
×2stories
+19ft-37ft

Overall

6615

Males

5955

M18-39

5955

Half→25K

13.1 - 15.5 mi

Top 26%
×4stories
+66ft-88ft

Overall

6928

Males

6107

M18-39

6107

25K→30K

15.5 - 18.6 mi

Top 38%
×9stories
+181ft-148ft

Overall

10214

Males

7935

M18-39

7935

30K→20M

18.6 - 20.0 mi

Top 26%
×5stories
+64ft-50ft

Overall

6825

Males

5865

M18-39

5865

20M→21M

20.0 - 21.0 mi

Top 24%
×8stories
+106ft-24ft

Overall

6449

Males

5521

M18-39

5521

21M→35K

21.0 - 21.8 mi

Top 27%
×7stories
+17ft-86ft

Overall

7163

Males

6003

M18-39

6003

35K→23M

21.8 - 23.0 mi

Top 30%
×5stories
+23ft-63ft

Overall

7944

Males

6379

M18-39

6379

23M→24M

23.0 - 24.0 mi

Top 33%
×6stories
+12ft-82ft

Overall

8714

Males

6732

M18-39

6732

24M→40K

24.0 - 24.9 mi

Top 65%
×1story
+6ft-20ft

Overall

17394

Males

10743

M18-39

10743

40K→25.2M

24.9 - 25.2 mi

Top 74%
×1story
+13ft-16ft

Overall

19594

Males

11718

M18-39

11718

25.2M→Finish

25.2 - 26.2 mi

Top 31%
×2stories
+22ft-21ft

Overall

8349

Males

6365

M18-39

6365

Passing Analysis

Category:
Athletes Passed
1090
Passed By
2241
Net Change
-1151
SegmentAthletes PassedPassed ByNet ChangeStart RankEnd Rank
Start → 5K----#6866
5K → 10K293120+173#6866#6693
10K → 15K19507-488#6693#7181
15K → 20K87182-95#7181#7276
20K → Half3811+27#7276#7249
Half → 25K11943+76#7249#7173
25K → 30K41449-408#7173#7581
30K → 20M13024+106#7581#7475
20M → 21M10633+73#7475#7402
21M → 35K4826+22#7402#7380
35K → 23M7863+15#7380#7365
23M → 24M4857-9#7365#7374
24M → 40K12426-414#7374#7788
40K → 25.2M2233-231#7788#8019
25.2M → Finish6967+2#8019#8017
TOTALS10902241-1151
📊

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