Emfit QS Installation & Operating Instructions Manual page 18

Green brackets indicate optimal range for each of the
classes, and total durations and percentages are also
given in numerical format.
All three stages have different physiological character-
istics, and their meaning to your body is different.
• LIGHT sleep is transitionary state from awake state
to DEEP sleep. Eyes are not moving, and muscle tone
is decreased.
• In DEEP sleep physical movement and muscle tone is
almost non-existent. Breathing rate is slow and steady,
heart rate is slow and blood pressure low. DEEP sleep
is essential for physical recovery and most physiolog-
ical systems in you are in a heightened anabolic state,
showing increased production of proteins, the essen-
tial building blocks needed for cell growth and repair
and rejuvenation of the immune, nervous, skeletal and
muscular systems.
• REM sleep is dreaming phase, characterized by rap-
id eye movements, paralyzed muscles, and variable
blood pressure and heart rate. REM sleep is needed
for mental recovery; during this sleep stage synaptic
connections can be re-organized, which enables learn-
ing, storage of memories, and forgetting unnecessary
things.
For complete recovery of your body and mind you
need to have sufficient amount sleep in general,
but also enough both REM and DEEP sleep.
REM sleep should constitute 20-25 % of your total
sleep, and DEEP sleep 10-20 %. This leaves some
50-60 % for LIGHT sleep.
4. HRV RMSSD
RMSSD, "Root Mean Square of Successive Differenc-
es", is one of the most widely used time domain heart
rate variability values. It tells about the activity of
our central nervous system, higher number indi-
cates better recovery, lower stress, etc.
We show both evening and morning values. Low
evening value tells that the day has been heavy, either
due to mental stress, or due to physical exercise. With
evening value athletes can see whether their training
has been effective.
Morning value should usually be higher than evening
value, indicating that there has been efficient recovery
and resting during the night. Mathematically, RMSSD
is the square root of the mean of the squares of the
successive differences between adjacent heart's beat-
to-beat intervals.
In the scientific literature RMSSD is widely accepted as
a measure of parasympathetic nervous system (PNS)
activity. According to Wikipedia, PNS is responsible for
stimulation of "rest-and-digest" or "feed and breed"
activities that occur when the body is at rest, and com-
plementary to that of the sympathetic nervous system
(SNS), which is responsible for stimulating activities
associated with the fight-or-flight response.
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For efficient recovery from training and stress, it is es-
sential that parasympathetic nervous system is active,
and our body gets sufficient rest and replenishment.
With HRV RMSSD value one can monitor what his/her
general baseline value is and see how heavy exercise,
stress, etc. factors influence it, and see when the value
gets back to baseline, indicating for example capability
to take another bout of heavy exercise. RMSSD can be
measured in different length time windows and in dif-
ferent positions, e.g. supine, sitting or standing.
Morning RMSSD value presented here is average of all
3 minute window RMSSD values measured during last
90 minutes prior to waking up. This should give you in-
dication of how ready and well rested your body is for
the new day. Evening value is similarly measured within
first 90 minutes in bed.
For more detailed analysis of full night HRV data you
can delve in to the details by using arrow button next
to i-button.
RMSSD value is highly individual and depends
on age, gender, fitness level, stress level, lifestyle
choices, etc. For this reason, one should monitor
values for a few weeks, and only after that make
conclusions on what kind of implications different
values have for him/her.
Generally, higher values indicate better health, fit-
ness, etc. In short term RMSSD indicates readiness
for the day, and in long term, for example along with
training, RMSSD values tend to climb up.
Long term decrease in RMSSD may be indication of
approaching over training condition.
5. TOTAL RECOVERY
Total Recovery is simply difference between morn-
ing and evening RMSSD values. Usually it should
be positive, indicating that there has been efficient
recovery and resting during the night.
Of course, this should be analyzed with regard to activ-
ities of previous day: if previous day was very light (no
stress, no heavy exercise) and evening RMSSD is rela-
tively high, it is not reasonable to expect high Recovery
number, because there is no load to recover from.
Values of Recovery are highly individual, and you
should inspect them against your own baseline values,
and also in comparison to Evening RMSSD values.
6. INTEGRATED RECOVERY
This is the total area of recovery during the whole night.
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