why 8 km @ 5:35 feels so easy and 5 x 1600 @ 5:25 so hard?

Perhaps what you are lacking is an accurately measured 8k route?

Do you know that the 8km was really 8km? If you ran it on a track, then of course you know for sure. But if you estimated the distance, then it could be off.

Also, keep the 1600 reps at 5:25 or better yet 5:24 (81 per lap) and keep it there then you won't blow up.

When you upped the pace to 5:25 /1600 you dropped 10 secs, but on the second and third rep you dropped it ANOTHER 7 seconds. Too much for you to handle with short rests.

As long as you can run the 8k at 5:35 avg. comfortably, try to run the 5 x 1600m in a disciplined 5:24 each time and don't go faster until you are better.

Yes, i used my GPS watch. Did the 1600 repetitions at exactly the same route. So even if there were 7.900 or 8100 by the GPS error than that would affect the 1600 as well.It seems that dropping 10 seconds is just too much for me. When I ran the 8k in 27:55 i ran very even paces of no faster than 5:31-32 and no slower than 5:39.any other ideas of type of trainings i could be doing to better that?

14-flat wrote:

Do you know that the 8km was really 8km? If you ran it on a track, then of course you know for sure. But if you estimated the distance, then it could be off.

Also, keep the 1600 reps at 5:25 or better yet 5:24 (81 per lap) and keep it there then you won't blow up.

When you upped the pace to 5:25 /1600 you dropped 10 secs, but on the second and third rep you dropped it ANOTHER 7 seconds. Too much for you to handle with short rests.

As long as you can run the 8k at 5:35 avg. comfortably, try to run the 5 x 1600m in a disciplined 5:24 each time and don't go faster until you are better.

Yeah, of course the avg. was 5:26 - BUT you had sub 5:20s in there. Sub 5:20 seems like faster than 5k pace for you. Just pace your workout better. Last one should be the fastest not some miles in the middle ;-) And to add something: I feel like 5 x 5:25s with 90'' jog are too fast on regular basis for a 33:50 10k runner. That's almost a race effort on regular basis (you aren't tapered for sessions). Not good. Just my opinion. Slow down the tempo and make it longer. Do the reps on more rest.

Ahhhh... Meant 10k pace.

Are these back to back sessions? If so I can only assume you tempoed too hard.

The long run was a steady-state effort which you couldn't complete without maintaining pH at an equilibrium level that maximized O2 unloading while minimizing acidosis.

The intervals were higher efforts than this, both aerobically and anaerobically. To increase your aerobic power beyond that long-run max, you had to use more acid-generating muscle to lower your muscle pH and make more oxygen available to it. Since you were only slightly over that threshold, the pH drop was slow but steady and once acidosis set in, it was too late. 90 seconds is not enough to fix it.

If you continue the intervals, eventually you may be doing your long runs at the same pace as you adapt to running that fast without excessive pH drop.

There's a million other factors too like temperature and time of day.

Actually, I experience this too. I won't say paces, but when I do a 5mile tempo, it feels comfortable. But 1k tempo intervals or mile intervals, even slower than my 5 mile tempo pace, feel dreadful.

Lack of speed work

You do understand that you are running near your threshold right?

toejam wrote:

background: 33:50 10k, 75:10 HM.

Training to beat my Half Marathon PR on april.

Averaging 50-60 miles per week.

Hope to run at least a 74:30, but actually aiming to reach the 73:XX

i am doing 3 key trainings per week: a long run at ~ 7:00 pace with some drills, a training where I simulate the HM effort and some 1600 intervals.

A 5:26 with rests seems so much harder than a 5:35 with no rest. It doesn't seem right. What I am lacking in my training?

Thanks!

Assuming that you are following all generally accepted training practices and not bs'ing, how about being more flexible in how you run the 1600s?

A 5:25 1600 is 81.25 seconds per lap. Run the first three laps with the idea of cruising at the pace of high 83 seconds (even 84 would be fine). That should feel real easy. Get to the fourth lap and then tell yourself to kick it in. I would not be surprised if you run 78 sec for the fourth. Jog another lap for recovery, and then start the mental practice again. Your total time will be only 5:30, but I am very confident that in just a few weeks of using this strategy, the first three laps will naturally drop to sub-80, and the fourth lap might even by 75.

This strategy has really helped me overcome training plateaus - especially when I employ it on a weekly basis.

Bad Wigins wrote:

The long run was a steady-state effort which you couldn't complete without maintaining pH at an equilibrium level that maximized O2 unloading while minimizing acidosis.

The intervals were higher efforts than this, both aerobically and anaerobically. To increase your aerobic power beyond that long-run max, you had to use more acid-generating muscle to lower your muscle pH and make more oxygen available to it. Since you were only slightly over that threshold, the pH drop was slow but steady and once acidosis set in, it was too late. 90 seconds is not enough to fix it.

If you continue the intervals, eventually you may be doing your long runs at the same pace as you adapt to running that fast without excessive pH drop.

There's a million other factors too like temperature and time of day.

Holy shit, you just exposed for good what a know-it-all moron you are. What are you 12 years old? More acid-generating muscle to lower your muscle PH? Sweet fancy Moses you are an idiot.

There are runners who are very strong aerobically but not very strong anaerobically. They can run all day at a steady pace, but uneven pace, or intervals really stress them. You can be very disciplined with your interval pace and only go slightly faster than you tempo pace or you can increase the rest interval -- 1:30 doesn't sound like much rest to me for a 1600 interval.

Les wrote:

There are runners who are very strong aerobically but not very strong anaerobically. They can run all day at a steady pace, but uneven pace, or intervals really stress them. You can be very disciplined with your interval pace and only go slightly faster than you tempo pace or you can increase the rest interval -- 1:30 doesn't sound like much rest to me for a 1600 interval.

This is not correct. The 8k workout was likely run at or around his lactate threshhold. It felt fine.

His repeats--especially the faster ones--were likely run above this anaerobic threshold. Once you get in that range, it doesn't take much effort to cross over the threshold.

Both workouts were primarily aerobic.

Rough rule of thumb: moving up (or down) in race distance should decrease (or increase) pace by about 15 seconds per mile.

Your tempo pace of 5:35 is approximately your HM pace. This makes your current 10k pace around 5:20. When I do 1600 reps at 10k pace, I use a 400 jog recovery.

I think you either went too fast for the recovery, or did too little recovery for the pace.

5:18 and 5:19 is considerably faster than 5:35.

1:30 sounds too short of a rest period try 2-2:30.

Try to negative split the miles or run even pace, like within 3-4 seconds.

Believe it or not running intervals at some distances like 400s and 1600s on the track raise the anxiety of the runner because they associate those distances with certain times and cannot run relaxed. Or they put more pressure on themselves because they're running on a "TRACK" and a track is supposed to be fast.

I've done 1600m intervals over the past year with two different training groups. One group was slower and one group was faster. It's actually been harder to run faster 1600s with the A group despite having people lead me around the track. The recovery was about the same. After analyzing the situations and conditions I came to the conclusion I was running much more relaxed with the B group. When running with the A group I would think about how slow I'm compared to them but when running with the B group that thought never crossed my mind. I had set up a mental barrier in my head when training with the A group which affected my 1600m intervals. I wasn't running relaxed and focused properly.

This is it. I promise you. You probably won't believe me because lots of distance runners don't think speed work has anything to do with them, or else think speed work is 800m reps. But if you run a simple workout like 400/300/200/100 with full recovery once per week, you will get a lot better in just a couple months. But you have to go pretty fast. Faster than 800 pace for the 400 if you're no good at the 800, and near 800 date pace if you are good. Then faster as you cut down. If you can't do this at first, do what you can control and watch yourself get faster each week.

Overall the session shouldn't kill you.

Try it and watch yourself get better.

14-flat wrote:

More acid-generating muscle to lower your muscle PH?

Lower muscle pH reduces the pH in the local blood supply, causing its hemoglobin to release more O2 into the muscle. That's why it's not possible to hit your max O2 consumption without crossing "lactate threshold," that is, lowering your muscle pH by using more, yes indeed, acid-generating, anaerobic-glycolytic muscle. And why it takes 30 seconds or more to get the aerobic system fully functioning during a run.

Don't pretend you knew that. And mind your manners on respectable threads, rude spineless lurker. Your sick obsession with me isn't the OP's fault.

When I ran my half PR:

Long run: 1:45-2 hours

Longer tempo: 8-10 miles

6 x mile @ 10k pace. 400 jog.

20-24 x 400 @ 5k dropping down to 3k pace at the end. 200 jog.

Other stuff in there but that's the basic formula.