Evaluation of Training Load During Suspension Exercise.

ABSTRACT: Giancotti, GF, Fusco, A, Varalda, C, Capelli, G, and Cortis, C. Evaluation of training load during suspension exercise. J Strength Cond Res 35(8): 2151-2157, 2021-The aims of this study were to evaluate body inclination and ground reaction force and to predict equations to estimate the training load distribution during suspension training (ST) static back-row at different lengths of the straps. Thirty volunteers (men = 16 and women = 14; age = 23.3 ± 1.7 years; body mass = 63.9 ± 13.3 kg; height = 167.9 ± 9.2 cm; body mass index [BMI] = 22.5 ± 3.4 kg·m-2) performed 14 static back-rows at 7 different lengths of the straps in 2 different elbow positions (flexed and extended). When the length of the straps increased, ground reaction force and body inclination decreased. Moreover, in the flexed elbow position, higher ground reaction force values were recorded with respect to the extended one. Two multilevel regression models (p < 0.05) were created. In the first one, ground reaction force was used as a dependent variable, whereas body inclination angle, body mass, height, BMI, and elbow position were used as independent variables. Significant (p < 0.05) effects were found for all variables included in the model, with an intraclass correlation coefficient (ICC) of 0.31. In the second model, the body inclination angle was replaced by the length of the ST device. Significant (p < 0.05) effects were found also in the second model for all variables included, with an ICC of 0.37. The proposed models could provide different methods to quantify the training load distribution, even if the use of the straps' length could result easier and faster than body inclination angle, helping practitioners and instructors to personalize the workout to reach specific purposes and provide load progression.

Dynamic Balance Evaluation: Reliability and Validity of a Computerized Wobble Board.

Fusco, A, Giancotti, GF, Fuchs, PX, Wagner, H, Varalda, C, Capranica, L, and Cortis, C. Dynamic balance evaluation: reliability and validity of a computerized wobble board. J Strength Cond Res 34(6): 1709-1715, 2020-Computerized wobble boards (WBs) are inexpensive, transportable, and user-friendly devices to objectively quantify the dynamic balance performances out of laboratory settings, although it has not been established if they are reliable and valid tools. Therefore, the purpose of this study was to determine the reliability and validity of a computerized WB. Thirty-nine (18 females and 21 males) young adults (age: 23.3 ± 2.1 years; body mass: 65.9 ± 1.8 kg; height: 168.2 ± 8.8 cm; leg length: 78.8 ± 5.7 cm; and body mass index: 23.2 ± 2.1 kg·m) participated in the study. Subjects were assessed during 3 separate sessions on different days with a 48-hour rest in between. A total number of 2 WB single limb tests and 1 Y Balance Test (YBT) were performed. The WB performance was registered using the proprietary software and represented by the time spent in the target zone, which represented the 0° tilt angle measured by the triaxial accelerometer in the WB. YBT normalized reach distances were recorded for the anterior, posteromedial, and posterolateral directions. Intraclass correlation coefficient, 95% confidence interval, SEM, minimal detectable change, and Bland-Altman plots were used to evaluate intrasession and intersession reliability, whereas Pearson product moment correlation was used to determine concurrent validity. Reliability ranged from fair to excellent, showing acceptable levels of error and low minimal detectable change. However, all correlation coefficients between WB and YBT outcomes were poor. Despite the 2 methods addressing different aspects of balance performance, WB seems to validly serve its purpose and showed good reliability. Therefore, computerized WBs have the potential to become essential devices for dynamic balance assessment.

Biomechanical Analysis of Suspension Training Push-Up.

Giancotti, GF, Fusco, A, Varalda, C, Capranica, L, and Cortis, C. Biomechanical analysis of suspension training push-up. J Strength Cond Res 32(3): 602-609, 2018-The aims of this study were to evaluate the load distribution between upper and lower extremities during suspension training (ST) push-up at different lengths of ST device and to predict useful equations to estimate the training load. After giving informed consent for participation, 25 subjects (17 men and 8 women; age = 28.1 ± 5.2 years; body mass = 69.4 ± 14.3 kg; height = 171.6 ± 11.3 cm; body mass index (BMI) = 23.4 ± 3.3 kg·m) were involved in the study. Each subject performed 14 static push-ups at 7 different lengths of ST device in 2 different elbow positions. The load distribution between upper and lower extremities was evaluated through a load cell and a force platform, respectively. To evaluate body inclination, all tests were recorded and analyzed through motion analysis software. To estimate the training load, a multilevel model regression (p ≤ 0.05) was used. Results showed that when the length of the ST device increased, the body inclination decreased, whereas the ground reaction force decreased and the load on the ST device increased. Moreover, when subjects moved from extended to flexed elbow, the ground reaction force decreased and the load on the ST device increased. In the created regression model (intraclass correlation coefficient = 0.24), the reaction force was the dependent variable, whereas the length of the ST device, BMI, and elbow position were the independent variables. The main findings were that the load distribution between upper and lower extremities changes both when modifying the body inclination and the length of the straps. The use of predicted equations could help practitioners to personalize the workouts according to different specific aims by modifying the length of the ST device to guarantee load progression.

1RM prediction: a novel methodology based on the force-velocity and load-velocity relationships.

PURPOSE: This study aimed to evaluate the accuracy of a novel approach for predicting the one-repetition maximum (1RM). The prediction is based on the force-velocity and load-velocity relationships determined from measured force and velocity data collected during resistance-training exercises with incremental submaximal loads. 1RM was determined as the load corresponding to the intersection of these two curves, where the gravitational force exceeds the force that the subject can exert. METHODS: The proposed force-velocity-based method (FVM) was tested on 37 participants (23.9 ± 3.1 year; BMI 23.44 ± 2.45) with no specific resistance-training experience, and the predicted 1RM was compared to that achieved using a direct method (DM) in chest-press (CP) and leg-press (LP) exercises. RESULTS: The mean 1RM in CP was 99.5 kg (±27.0) for DM and 100.8 kg (±27.2) for FVM (SEE = 1.2 kg), whereas the mean 1RM in LP was 249.3 kg (±60.2) for DM and 251.1 kg (±60.3) for FVM (SEE = 2.1 kg). A high correlation was found between the two methods for both CP and LP exercises (0.999, p < 0.001). Good agreement between the two methods emerged from the Bland and Altman plot analysis. CONCLUSION: These findings suggest the use of the proposed methodology as a valid alternative to other indirect approaches for 1RM prediction. The mathematical construct is simply based on the definition of the 1RM, and it is fed with subject's muscle strength capacities measured during a specific exercise. Its reliability is, thus, expected to be not affected by those factors that typically jeopardize regression-based approaches.

Wobble board balance assessment in subjects with chronic ankle instability.

BACKGROUND: Wobble boards (WBs), commonly used to train postural control, have been recently equipped with accelerometers connected to a computer displaying real-time balance performances. However, little is known about their ability to detect balance deficits in subjects with unilateral chronic ankle instability (CAI). OBJECTIVE: To determine if computerized WBs can detect balance deficits in subjects with unilateral CAI. METHODS: Fifteen subjects with unilateral CAI and fifteen uninjured subjects performed one WB test and one Y Balance Test (YBT) during two separate randomized sessions. WB performance was assessed as the time (s) spent on the platform by keeping it flat at 0° during three 30-s trials for each limb. Normalized (%) reach distances values for anterior, posteromedial, posterolateral directions and composite were recorded for YBT. RESULTS: WB has been shown to be a reliable and accurate device for detecting balance deficits between and within subjects with unilateral CAI. The area under the curve for receiver operating characteristic was 0.80 (asymptotic significance 0.001), suggesting that WBs have the capability to accurately discriminate between injured and uninjured limbs. SIGNIFICANCE: Computerized WBs can fill the gap caused by limitations between subjective-based clinical assessment and laboratory-based testing, especially in field-based settings, where specificity, transportability and time constraints are crucial. The results of the present study suggest that WBs may facilitate the detection of balance impairments in subjects with unilateral CAI, without complexity in its use or data interpretation.

The Role of Velocity Based Training in the Strength Periodization for Modern Athletes.

Resistance training (RT) is considered the most important method to improve the athlete's strength and rate of force development (RFD). In the last decade, the importance of monitoring velocity during RT has drastically grown, because of an increased availability of linear position transducers (LPT) and inertial measurement units (IMU). The purpose of this review is to analyze the existing literature on testing techniques and performance strategies used to enhance strength and power performance of elite athletes, by monitoring the velocity of resistance training. The authors focus in particular on the level of effort of resistance training defined by velocity; how the loss of velocity correlates with the degree of fatigue and how it can be used to enhance the performance of competitive athletes; the use of LPT as part of the daily routine of the strength and conditioning programs in competitive sport. It is therefore critical for the sports scientists to have a correct understanding of the basic concepts of the velocity-based training and their application to elite sports. The ultimate goal is to give some indications on the velocity-based resistance training integration in the programs of different sports in the high performance environment.