@ChopWoodAndCarryWater
Fair play 💚🤗
@ChopWoodAndCarryWater
Did you enjoy it ? I enjoy mixing in speed intervals ocassionally usually after gentle jog warm up or just as a set of progression ones 😉
@RunningMachine I did enjoy it.
@ChopWoodAndCarryWater
Do you know what your max hear rate is ? your heart rate seems pretty high. It appears like your doing a 3 minutes or so warm up. most runners say 'the first mile always lies', you might find it more comfortable with 6-7 min warm up and a couple of slower intervals at the start to lift heart rate a little slower before taking it so high.
@RunningMachine 
@ChopWoodAndCarryWater
Based on the 220-age formula, which isn't particularly accurate that would suggest you are late teen early twenties so that hitting 175 isn't so bad.
What are you trying to achieve with speed intervals ? 1.6 km in 15 mins seems relatively slow pace for the heart rates your reaching, most days, being much older and just maintaining fitness, weight control I'm running 10-12 km in an hour at an average of 124 bpm.
@RunningMachine I turned 37 in October.
@ChopWoodAndCarryWater
I'm off out for a while, what are you aiming to achieve ?
@RunningMachine Improve VO2 Max.
@ChopWoodAndCarryWater
If you check my profile you'll see I've got a lifetime of experience as an athlete, I'm quite happy to help if you would like me too.
There is modern trend of training VO2 max in particular that I consider a little dangerous in itself. I agree fully with Hit style workouts to raise it but only from a reasonable level of fitness and aerobic base, in my opinion it is too stressful on the heart in particular if the base work isn't there. How much base training do you do are you anywhere near the 80/20 split ?
@RunningMachine That 80% doesn't exist for me. This 20% is my 100%.
@ChopWoodAndCarryWater This was in July.
@ChopWoodAndCarryWater
In that case then I'd suggest your session is to intense, average walking pace is 4.8 to 6.4 Km/HR.
Maybe give his a try, walk at 5.6 km/HR for 5-6 mins, heart will likely increase gradually, plateau and maybe dip slightly but then try even intervals 1 minutes on 1 minute of, start at 8/5.6 then 9/5.6 etc and see what your heart rate does. You might find it a bit more comfortable, but your heart will thank you for the longer warm up.
When you start exercise the heart responds by increasing the stoke volume by contracting stronger and by increasing pace. By lengthening your warm up you are encouraging to contract more efficiently before just beating quicker, it might help you avoid the aerobic shock that often happens when you start to quickly.
@RunningMachine This is the default program that I've been following. 
@ChopWoodAndCarryWater
My observation from earlier still stands, i find Hit a little risky when it doesn't consider base fitness first. The overall objective is on point provided the base level is already there to work from.
@RunningMachine What'd be the base level required to safely go for HIT?
Any benchmark time for a km run?
@ChopWoodAndCarryWater
What is your general activity levels like, walking, work etc are you overweight or a healthy weight and are you combining it with resistance, functional or mobility training too...
From my extensive experience high intensity intervals puts too much strain on the heart if it hasn't got sufficient development.
I I had clots in my lungs in 2015 & 2017 and have recovered full fitness since. I have an annual VO2 max test every January as part of a Thrombosis (blood clot) research project, this year I manged to post 72 which is very high for a 59 year old but my I've developed an athletes heart from over 40 years of training.
I'm skinny fat. 
@RunningMachine An uninterrupted treadmill session of longer than 20 minutes is not allowed at the gym I go to.
@ChopWoodAndCarryWater
Easily solved, 20 min treadmill, the same on rower and cross trainer, or equivalents 😄
Being a former racing cyclist I love the spin classes and tend to hit my intensity sessions on it 😄😄
@RunningMachine Not much of those step counts have been runs. I've not been a regular runner.
@ChopWoodAndCarryWater
That was way triggered me to respond,, I was struggking to see what the purpose of 1km Hit a day was for.
Short high intensity Hit sessions work if you have a good endurance based or are mixing them in with longer low intensity base work as one works the aerobic system and the Hit targets anaerobic tolerance. Both will lify tour VO2 max over time.
High intensity work works better with resistance training, as recovery and building muscle works better with it. Too much low resistance CV impairs muscle growth as it isn't stimulated enough to grow.
My initial questions was about your objectives, you stated raising your VO2 max, I'm interested why ? VO2 max is literally the maximum volune of oxygen your blood can absorbed at maximum intensity, wrist bases activity trackers etc can only estimate bases on age standards, pace, duration and heart rate which is merely an estimation and even popular brands like Garmin, Polar etc aren't accurate. With my past I can't trust them at all as they would be miles off
If you have got limited time to train and nut training to compete on races, then for the benefit of your heart, i.e lower stress, I would recommend splitting your training a little at least
My current focus is ultimatey to lift keep my blood circulation as optimal as I can, slow steady warm up so it contracts fully before lifting pace a little upto the top end on my aerobic zone. I then do walk/run intervals keeping heart rate within Zone2. It works as a staple run I can repeat daily, keeps heart in shape while maximise fat burning, both designed to minimise my risk of Thrombosis.
I'm happy to help tailor a plan with you if you would like ? I remain a little concerned that without a solid aerobic pace, daily 1k Hit sessions on their own is just unnecessary strain with minimal gain.
@ChopWoodAndCarryWater
As an aside, it's also worth focusing on breathing, in through the nose ( nasal passages filter nitrogen monoxide) ans out through the mouth. If you focus on forcing the out breath you are clearing more CO2 which is what essentially triggera your heart rate rise, the less NO and CO2 in your blood the easier it can absorb oxygen. Also by forcing the whale you are effectively creating a vacuum effect which makes the inhalation more effective.
One of the factors that surprises me most 40 years ago, is that on average even professional level athletes with really high VO2 Max's only absorbed no more the 70% of the oxygen inhaled each breath.
@RunningMachine I keep it a point to keep my mouth shut during HIT. I, inhale and exhale from my nostrils only. Never from my mouth. When I can breathe no more, I pull the lever.
