Effects of Resistance Training With High vs. Light-moderate Loads on Muscle-tendon Function in the Elderly
Effects of Resistance Training With High vs. Light-moderate Loads on Muscle-tendon Function in the Elderly
There are no unbiased studies that have analyzed the effects of resistance training with
 traditional, heavy versus light-moderate loads on muscle, tendon and bone in elderly people.

 The purpose of the present study is to assess the effects on muscle mass and function, tendon
 and bone of two different training intensities, light-moderate vs. heavy load, in people
 older than 65 years old.

 The study will be carried out with a randomized controlled design. Participants will perform
 single training sessions and a 12-wk dynamic resistance training program on the knee
 extensors with different training intensities on each leg. One leg will train with heavy
 loads and the other one will train with light-moderate loads, but matching the load x
 repetitions performed by the contralateral side.
The decline in muscle function provoked by the aging process and frailty are directly related
 to decreases in mobility and the ability to perform the so called "daily life activities".
 Resistance training is especially useful at this stage, given that it is an effective and
 widely applicable intervention to control and revert sarcopenia, and the deterioration of
 tendon and bone function. Despite of the effectiveness of heavy load resistance training, a
 controversy has arisen in the last years about the effects of lower load resistance training
 programs to achieve similar adaptations. This is because most of the studies that have
 compared light-moderate versus heavy load programs did not control the differences in total
 training load, measured as the overall mechanical work performed during the training program.
 Therefore, there are no unbiased studies that have analyzed the effects of resistance
 training with traditional, heavy versus light-moderate loads on muscle, tendon and bone in
 elderly people.

 The purpose of the present study is to assess the effects on muscle mass and function, tendon
 and bone of two different training intensities, light-moderate vs. heavy load, in people
 older than 65 years old.

 The studies will be carried out with a crossover (acute training sessions) and randomized
 controlled design (longitudinal training intervention). Participants will perform single
 training sessions with each resistance training intensity and a 12-wk dynamic resistance
 training program on the knee extensors with different training intensities on each leg. One
 leg will train with heavy loads and the other one will train with light-moderate loads, but
 matching the load x repetitions performed by the contralateral side. Muscle adaptations (EMG,
 muscle size and architecture), tendon mechanical properties, bone mineral density, blood
 parameters and life quality will be analyzed before and after the cessation of the training
 program.
Inclusion Criteria:

 -  65 years and older,

 -  non-institutionalized

 -  passed physical examination including physical function assessment (no frailty status;
 SPPB >7 points)

 Exclusion Criteria:

 -  Neurological, musculoskeletal, or other disorder that would preclude completing
 resistance training and all performance tests

 -  Uncontrolled hypertension, unstable or exercise-induced angina pectoris or myocardial
 ischemia or any other medical condition that would interfere with testing or increase
 one's risk of complications during exercise.

 -  History of regular resistance exercise during the previous 3 years

 -  Knee prosthesis