Liza is an iPhone App aimed at measuring muscle performance. The user can get information (maximum power, 1RM and others) from the performed workout session. Liza uses the accelerometer integrated in the iphone/ipod touch to record the acceleration during the execution, calculating then speed and other output data.

1. LIZA
Measuring muscle power with iPhone

2. ABOUT EXELIO
• Alessandro, Marco and Valerio are
bound by their common skills in
computer science and passion for
sport.
• The desire to create their own business
and to make their passions profitable
drove them to give life to Exelio.
• The vision is: “for each sport and each
sportsman a device and a software to
measure his performances”.
• Their first project is Liza.

3. THE IDEA
DEVELOPING:
• a simple and cheap solution to measure the
muscular performance.
• a professional test at everybody’s reach
USING THE IPHONE/IPOD TOUCH:
• accelerometer integrated
• flourishing AppStore market (3 billion
downloads)
• originality: there is no other application like this

4. THE APP
An IPhone/IPod touch application that measures
muscle power.
Two exercises may be used by the first version of
Liza:
• half squat
• bench press
After fixing the device to the gym machine (barbell),
proceed with the test as explained by Liza. After few
minutes you will know:
• Max Power
• Speed and load at max power
• 1RM

5. HOW DOES IT WORK?
• Liza works using the builtin
accelerometer inside the iPhone
or iPod touch.
• Liza calculates speed from
acceleration during the exercise
and consequently the other
parameters.
• Liza uses some sophisticated
algorithm to filtering the signal
and produce an accurate result.

6. ACCELEROMETER SIGNAL
acceleration - speed - force - power
f=m*a p=f*v

7. PROTOCOL TEST
• Load-predetermined based
on user profile
• Four sets with increasing load
• Threerepetitions per
set(best selection)
• Executethe repetitions to
the max speed

8. TEST RESULTS
• Max Power
• Liza index
• Trend
• Load at max power
• Speed at max power
• 1RM
• Max relative power

9. POWER MEASUREMENT
• Mostaccurate indicator because every sport movement
needs a combination of strength and speed
• Power measurement is already a standard for physical exertion
of elite athletes
• Liza makes power measurements accessible to everyone

10. LIZA INDEX
• easy evaluation of your
performance
• user’s quality of muscular
performance index on a scale
from 1 to 10
• based on user specific profile
(sex, age and weight)
• for the same athlete it can be
different for squat and bench press

11. ONE REPETITION MAXIMUM
• maximum load that the athlete
is able to lift in a single set
performed at maximum intensity
• no need for the athlete to
personally perform the excercise
to doublecheck the top load he
can lift
• value estimated comparing load/
speed relationship in test
execution

12. GRAPHIC REPRESENTATION
relationship between load and speed
relationship between load and power

13. READING THE GRAPH
Rapid force: exercise execution time (single lift) < 0,150 sec, load 0 – 23% 1RM, repetition number possible with maximum engagement 35-28
Explosive force: exercise execution time from 0,150 to 0,300 sec, load 24 – 43% 1RM, repetition number possible with maximum engagement 27 – 23
Dynamic force: exercise execution time from 0,300 a 0,700 sec, load 44 – 74% 1RM, repetition number possible with maximum engagement 22-10
Maximum force: exercise execution time > 0,700 sec, load > 75% 1RM, repetition number possible with maximum engagement 9-1

14. WHY SHOULD I USE LIZA?
• Monitoring my muscle
performances gives me a feedback
about my training program
• I will know the best load to use
for my muscle empowerment
according to the sport I usually
practice and to my goals
• I can check my improvements
repeating my test month by
month

15. FEATURES OVERVIEW
• Accelerometer calibration
• Multiuser
• Two exercises
• Test protocol
• Real time repetition feedback
• Immediate evaluation
• Muscle curve
• Send email
• Twitter
• Test comparison
• Report

16. TEST COMPARISON
Expected training effects:
• Same load lifted faster
• At the same speed I produce
more power
• At the same load I produce more
power
• I reach the maximum power with
higher load and higher power

17. LIZA VERSIONS
• Lite vs Pro
• Lite for free
• both tests (half squat and bench
press), to view the resulting data
and send them via email or twitter
• not possible to get any graphic
representation nor save any data
• Pro version ($ 19.99)

18. NEXT STEP
• Exercise feedback
• New exercises

19. CREDITS
• EXELIO idea and production
visit website liza.exelio.eu
• SINE graphic design
• DATAMIND interface
development