RAGT may significantly improve walking ability, motor function and for a maximum period of three months. Thus, our findings support the importance of a RAGT as a valid rehabilitative tool for PD.

Evaluating the rate of torque development (RTD) in isometric ballistic contraction targeting submaximal torques is usually overlooked in the literature. In a series of isometric ballistic contractions targeting a range of submaximal torque values, there is a linear relationship between the peak torque and the peak RTD obtained in each contraction. RTD scaling factor (RTD-SF) represents the slope of this relationship. In this study, we investigated the prevalence of interlimb asymmetry in the RTD-SF and in the RTD calculated across submaximal torques. Furthermore, we compared these asymmetry indices with those calculated adopting more classical approaches, such as ballistic contraction targeting maximal torque and isokinetic concentric conditions. Quadriceps and hamstrings strength was evaluated in both limbs of elite under 17 and under 19 soccer players (20 males, 17 ± 1 years). Participants performed three concentric isokinetic contractions at 240°/s and a series of isometric ballistic contractions targeting from 20 to 100% of maximal isometric torque. The interlimb difference was calculated for each parameter and players presenting an interlimb difference >15% were identified. A total of 40% (for quadriceps) and 60% (for hamstring) of players showed an interlimb asymmetry in isometric RTD for at least 50% of submaximal torque range. The RTD-SF was able to identify more players with asymmetry than the classical isokinetic tests. However, isokinetic and isometric indices of asymmetry were in general poorly or not correlated with each other. Most players presented an interlimb asymmetry in RTD for a wide part of the torque range and the adopted protocol was able to highlight important interindividual differences. Furthermore, players showed a large prevalence of RTD-SF asymmetry in both quadriceps and hamstrings. It is still to be determined if these asymmetries are functionally relevant. Nevertheless, the adopted protocol provided meaningful information for identifying interlimb asymmetries that could not be gathered when adopting the classical method of ballistic contractions targeting only maximal torques.

Objective: The neuromuscular quickness capacity can be assessed calculating the rate of torque development (RTD) during ballistic contractions of maximal (RTDmaximal) or submaximal (RTDsubmaximal) amplitudes. In a series of ballistic contractions of submaximal amplitudes, RTD scaling factor (RTD-SF) represents the slope of the linear regression between achieved peak torques and the corresponding RTD. We firstly investigated if the RTD-SF contributes to predict, together with maximal voluntary torques (MVT), the RTDmaximal. Then, we evaluated the agreement between the z-scores of RTDmaximal and RTDsubmaximal.Approach: MVT of quadriceps and hamstrings muscles were obtained in 22 elite young soccer players. RTD-SF was quantified in a series of ballistic contractions of submaximal and maximal amplitudes. RTDsubmaximal was estimated from the regression relationship between the peak torques and the corresponding RTD.Main results: MVT, RTD-SF and y-intercept accounted all together for 76.9 and 61.2% of the variance in RTDmaximal in quadriceps and hamstrings, respectively. Specifically, RTD-SF accounted for 13.7% and 18.7% of the variance in RTDmaximal respectively. Generally, the agreement between the z-scores of RTDmaximal and RTDsubmaximal was poor both in quadriceps and hamstrings.Significance: These results suggest that RTD-SF may have a functional relevance in the relationship between MVT and RTDmaximal and influence the amount of torque that can be achieved in a quick muscle contraction. Moreover, evaluating the RTDsubmaximal does not provide interchangeable results with RTDmaximal. Thus, evaluating the RTD across the whole range of torque could provide additional meaningful information about neuromuscular quickness.

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