6). Figure 6. B-line reproduction by hydration of gelatin samples using different controlled water selleck 17-AAG volumes. One 10 ��L drop (A) and two drops (B) spaced about 1 cm apart. Materials and Methods Materials All materials were purchased from Sigma-Aldrich. A 5% w/v gelatin solution was prepared by dissolving gelatin (Type A) in deionized water dH2O stirring the solution for 1 h at 50��C. A batch cross-linking solution of glutaraldehyde (GTA) in water was prepared with a concentration of 0.1 M and used for sequential dilution. A 40% v/v ethanol: dH2O solution was used to rinse samples. Preparation of porous gelatin matrices Gelatin sponges were prepared to evaluate the porosity and mechanical properties as functions of cross-linking conditions as well as to recreate B-lines in an in vitro model.

In particular, the preparation method was divided into two steps. In the first step gelatin was cross-linked using GTA with different concentration (nominated GC); then, in order to obtain a porous matrix, a freeze-drying process was used as described by Lien et al.17 Briefly GTA was added to a 5% w/v gelatin solution to obtain a final volume of 1 mL and 0.1, 1 and 10 mM GC scaffolds were fabricated. The scaffolds were kept in a plastic tube (internal diameter 12 mm) at 25��C for 12 h, until the cross-link reaction had occurred. Two cooling steps were used to freeze the samples; the first step in a refrigerator at 4��C for 6 h and then the second step in a -20��C freezer over-night. Finally samples were freeze-dried (-50��C, 150 mBar) until all water content was removed.

Measurement of swelling ratio The water absorption capability of porous gelatin structures was determined by immersing freeze-dried samples in water for 1, 24 and 48 h. The swelling ratio was calculated according the following equation (Eq. 1): In which Wd is the air-dried scaffold weight and Ww is the weight of the wet scaffold.10 Porosity evaluation The porosity was evaluated by imbibition method and was assumed as the gelatin volume fraction in the swollen samples (). Through the water saturation, pore volume was evaluated by weighing swollen and dried samples. The gelatin volume fraction was calculated according to Equation 2:18,19 in which W0 is the dry weight of the sample, W is the weight of the swollen sample, ��w is the density of the water at RT (room temperature), and �� is the density of the dry gelatin sample.

Pore dimension was evaluated through histological analysis. Samples were embedded and fixed in Tissue-Tek O.C.T. before cryo-sectioning. Horizontal sections of 10 ��m thickness were obtained from the cylindrical scaffolds and then observed with an optical microscope (Olympus IX81, Olympus Italia, 4X objective). Measurement of mechanical properties Compressive mechanical tests were Batimastat performed using a twin column testing machine Zwick-Roell Z005 Instron (Zwick Testing Machines, Ltd.).

049) (ES �� 0.97). Figure 2 Example of raw selleck EMG of rectus femoris (RF), vastus lateralis (VL), and vastus medialis (VM) after different acute stretching methods (pre-static, post-static, pre-dynamic, and post-dynamic) during soccer instep kicking Figure 3 Mean �� SD changes in rectus femoris, vastus lateralis, and vastus medialis root mean square EMG during soccer instep kicking before and after static and dynamic stretching. Significant at p < 0.015, Significant at p < 0.004, Significant ... Table 2 Mean (�� SD) muscles activity, knee and ankle joints angular velocity, and foot and ball velocity descriptors of the soccer instep kicking after different acute stretching methods KAV showed a significant increase by 9.65% �� 4.92% after dynamic stretching (p = 0.002) versus a non-significant change (?1.

45% �� 4.84%) after static stretching (ES �� 0.98). Dynamic stretching (10.12% �� 5.32%) also showed greater AAV than static stretching (?3.29% �� 3.68%) (p = 0.011) (ES �� 0.96). In addition, dynamic stretching (10.77% �� 7.12%) caused significantly faster BV when compared to static stretching (?6.56% �� 3.67%) (p = 0.001) (ES �� 0.99). Discussion The main finding of this study is that, compared to static stretching, dynamic stretching of the quadriceps resulted in a higher increase of (1) VM, VL and RF muscle activation, (2) maximum knee and ankle angular velocity and (3) maximum ball velocity during an instep soccer kick. Further, dynamic stretching caused a higher increase of RF muscle activity as opposed to VM and VL muscles. The present results support previous research studies (Cramer et al.

, 2005; Marek et al., 2005) indicating that dynamic stretching increases activation of all superficial quadriceps muscles more than static stretching (Figure 3). However, in contrast to previous research studies, our results refer to a multiarticular movement, such as the soccer kick and therefore, direct comparison between the aforementioned studies is difficult. Particularly, backward and forward swinging motion of the kicking leg is mainly accompanied by a fast stretch-shortening cycle of the quadriceps (Bober et al., 1987). Along with the motion-dependent moments, the knee extensors provide the main force in order to accelerate the shank during the forward motion of the kicking leg (Kellis et al., 2006; Dorge et al., 1999).

A higher quadriceps activation and strength, coupled with a more efficient stretch-shortening cycle probably lead to a higher AV-951 maximal KAV (Kellis and Katis, 2007; Kellis et al., 2006) which is transmitted to the ankle and finally to the toe and increases ball speed (Asami and Nolte, 1983). Consequently, any changes observed after stretching should be related to some or all the aforementioned factors. In the present study, quadriceps muscle EMG (Figure 3) remained unaltered while angular and ball speed kinematics decreased after static stretching.

None of the participants had performed regular leg strength exercise in the previous 3 months. These criteria were created in order to avoid protection selleck kinase inhibitor against DOMS from repeated bouts of resistance exercise. Eligible participants were randomly assigned into one of three groups; a warm-up group, a cool-down group, and a control group. Group characteristics at baseline according to group allocation are presented in Table 1. The allocation of participants was performed by random draw with men and women being assigned separately. The study was approved by the Regional Committee for Medical and Health Research Ethics (S-2009/1739-1, REK midt, Norway) and carried out in accordance with the Declaration of Helsinki. Table 1 Group characteristics at baseline according to group allocation.

Measures and Procedures Measurements were carried out on three consecutive weekdays with similar test time on each day (<2 hours difference between days). All participants performed a bout of front lunges on day 1. This resistance exercise imposes eccentric lengthening of the quadriceps muscle during the braking phase but also requires a concentric effort during the push-off phase. Precise and consistent description about the performance technique was given to each participant. The exercise was standardized by marking the individual stride length in the bottom position of the lunge when assuming a ~90�� angle in the knee and hip joint of the forward stepping leg. The exercise was performed with the dominant leg only, i.e., the forward stepping leg, in 5 sets with 10 repetitions with 30 sec rest between each set.

A metronome was used to ensure participants maintained a cadence of 10 lunges per 30 sec. External load was provided by a barbell held behind the neck on top of the shoulders. The load was set to 40% and 50% of the body mass for woman and men, respectively. Recordings of pressure pain threshold (PPT), maximal knee extension force during maximal voluntary isometric contraction (MVC), and subjective ratings of muscle soreness on a visual analogue scale (VAS) were carried out before the front lunge exercise (day 1), 24 hours after exercise (day 2), and 48 hours after exercise (day 3). All recordings were carried out for the exercised leg only. Prior to the front lunge exercise on day 1, the warm-up group completed 20 min of moderate intensity aerobic exercise.

Conversely, for the cool-down group, the front lunge exercise was followed by 20 min of moderate intensity aerobic exercise. The control group Dacomitinib only performed the front lunge exercise. The warm-up and cool-down were done on a cycle ergometer (Monark 939E, Vansbro, Sweden). The first 5 min of cycling was used to adjust the workload to correspond to ~65% of estimated maximum heart rate (HRmax adjusted for age; 220-age * 0.65). The last 15 min was performed at a workload of 60�C70% of HRmax with a cadence of 65�C75 rpm.

50 > BMI more information > 24.99) according to WHO classification (WHO, 2004). Likewise, in case of weight/height indices, mean body fat percentage recorded in climbers was comparable to this observed in untrained students and amounted to 15.4%. However, when classified by Heath-Carter somatotype components, endomorphy component that reflects adiposity had the lowest contribution in climbers�� somatotype; the mean value being significantly (p<0.001) lower than that observed in untrained students (2.4 �� 0.79 vs. 3.6 �� 1.48, respectively). Regardless of comparable body height, climbers had significantly greater arm span and arm length (by about 6 and 2.5 cm, respectively) what was reflected in ape index and arm length index, the respective values being by about 1.5 (p<0.001) and 0.6 SD (p<0.

01) greater than observed in untrained students, respectively. Additionally, climbers exhibited significantly greater values in arm (32.7 �� 2.09 vs. 30.9 �� 2.52 cm) and forearm circumferences (28.3 �� 1.28 vs. 26.02 �� 1.80 cm) and in upper extremity girth index, while no differences were found for elbow width. On the other hand, climbers had by 1 SD (p<0.001) lesser knee width while no between-group differences were found for calf circumference. Moreover, climbers exhibited by about 1 SD less in pelvis-to-shoulder ratio comparing to untrained students. Likewise, for upper extremities climbers had significantly (p<0.05) longer lower limbs as expressed by the Manouvrier��s index. In order to reveal possible relationships between somatic indices and subjects�� climbing ability, Pearson��s correlation coefficients and partial correlations were calculated.

Apart from the obvious relations between the body fat and weight-to-height indices or between indices pertaining to the length of upper limb, significant negative correlations were found only for %FAT and ape index (?0.594; p<0,01) and for arm circumference index and BMI (r = ?0.497; p<0.05) or RI (r = ?0.587; p<0.01). Self-reported climbing ability significantly correlated with %FAT (r = ?0.614; p<0.01); besides that, no significant correlations with somatic indices were noted and none of the partial correlations proved significant. Only the ape index tended to correlate with the self-reported climbing ability (r = 0.397; p = 0.083). Discussion Despite the growing number of reports on rock climbing, those concerning anthropometric characteristics of climbers are rather scarce and inconsistent.

The results of this study do not support the view of Watts et al. (2003) that climbers are small in stature with low body mass as no differences between the climbers and untrained controls were found for basic Cilengitide somatic features and body size-related indices. Body height and body mass of climbers were rather average and amounted to 180.0 cm and 70.7 kg, respectively, what was in line with the observations of Billat et al. (1995) and Grant et al.