*2.2. Instruments*

Adherence to a Mediterranean Diet Questionnaire (KIDMED): The KIDMED questionnaire, previously validated, was used to evaluate the adherence to MD in adolescents (http://www. aulamedica.es/nh/pdf/9828.pdf). The questionnaire consists of 16 items, where 12 questions assume a positive score for adherence to MD (consumption of yogur<sup>t</sup> and dairy products, consumption of legumes, use of olive oil, consumption of vegetables, fruits, fish, cereals, rice, pasta, and nuts) and four questions assume a negative score (consumption of fast food, not having breakfast daily, consuming sweets several times a day, consuming industrial pastries). Affirmative answers to questions that represent a negative connotation in relation to the MD are worth −1 point and affirmative answers to questions that represent a positive aspect in relation to the MD are worth +1 point. Negative answers do not score [50–52].

Therefore, this index can range from 0 (minimum adherence) to 12 (maximum adherence). The sum of the values of this questionnaire gives rise to the KIDMED index, which is classified into three categories: From 8 to 12: an optimal MD (high adherence); from 4 to 7: a need to improve the food pattern to adapt it to the Mediterranean model (average adherence); and from 0 to 3: a very low-quality diet (low adherence) [50–52].

Alpha Fitness test battery: Physical fitness and anthropometric variables were assessed by a modified version of the extended ALPHA fitness test battery, (Ref: 2006120)). Skin folds were omitted for limited time reasons and the 4 × 10 m speed-agility test was added to the version in order to have more information about physical fitness. The protocol marked on the ALPHA-Fitness Battery for measurement was followed at all times [53].

Body composition: The height of the subjects was recorded barefoot with an accuracy of 0.1 cm using a portable stadiometer (Seca 213, Seca, Hamburg, Germany). The weight of the participants was measured with an accuracy of 0.10 kg, the subjects wore light clothing, and a portable electronic scale was used. Body fat percentage (BF%) was measured by bioelectrical impedance (Tanita Inner Scan BC-543, Tanita, Tokyo, Japan). Body mass index (BMI) was calculated from the ratio of body weight (kg) to body height (m2). Waist circumference was measured with a non-flexible measurement tape (Seca 201, Seca, Hamburg, Germany) with the adolescent standing upright and with an accuracy of 0.1 cm. The measuring point was the narrowest part of the space between the lowest rib and the anterior superior iliac spine at the end of normal expiration.

Cardiovascular fitness was assessed with the multistage 20 m shuttle run test (Leger et al., 1988) [54]. In this test, the participants had to run a distance of 20 m, adjusting their speed to the rhythm of the audio signals that were emitted from a previously recorded CD. The subjects finished the test when they could not reach the line a second time concurrent with the audio, or when the subject stopped due to fatigue. The initial speed was 8.5 km/h, with this being increased by 0.5 km/h per minute [55].

Lower body explosive muscle strength was assessed using a standing long jump. The participants, placed behind the jumping line with their feet together, pushed hard and jumped as far away as possible, contacting the ground with both feet simultaneously and in a vertical position. The distance

was measured from the rearmost heel to the jumping line and was always performed on a non-slippery surface.

Upper body maximal muscle strength was measured by means of handgrip strength using a hand dynamometer with an adjustable grip (TKK 5401 Grip D, Takey, Tokyo, Japan). The examiner showed the correct way of execution and adjusted the grip measure according to the size of the hand [56]. The test was performed twice, and the best result was recorded, calculating the average of the two hands. The subjects were verbally encouraged to "squeeze as hard as possible" and to exert the maximum effort for at least two seconds (s). Speed-agility was tested using the 4 × 10 shuttle run test. The examiner showed the correct way of execution. The test was performed twice, and the best result was recorded (s). The participants had to run, as fast as possible, the distance between the two lines placed 10 m away, change a series of sponges (three times), and run back to the starting line.
