Paula Marta Bruno

The impact of exercise training on liver transplanted familial amyloidotic polyneuropathy (FAP) patients.

Background Liver transplantation is nowadays the only effective answer to adjourn the outcome of functional limitations associated with familial amyloidotic polyneuropathy (FAP), a neurodegenerative disease characterized by sensory and motor polyneuropathies. Nevertheless, there is a detrimental impact associated with the after-surgery period on the fragile physical condition of these patients. Exercise training has been proven to be effective on reconditioning patients after transplantation. However, the effects of exercise training in liver transplanted FAP patients have not been scrutinized yet. Methods The study aimed to evaluate the effects of a 24-week exercise training program (supervised or home-based) on body composition, muscle strength, and walking capacity of liver transplanted FAP patients. To fulfill this goal, a sample corresponding to 33% of all FAP patients who undergone a liver transplantation in the area of Lisbon between January 2006 and December 2008 were followed over time. Three evaluation periods were accomplished: M1 (pre-exercise training period), M2 (immediate post-exercise training period), and M3 (24 weeks after M2). The former allowed an assessment of the impact of detraining in these patients. Results The exercise training program improved body composition (lean mass and total body skeletal muscle mass), weight, and walking capacity. The improvements were more pronounced within the patients with supervised exercise training compared with the patients on the home-based program. In general, the benefits of the exercise training perdure even after a 24-week detraining period. Conclusions Exercise training results in significant improvements on the physical condition of liver transplanted FAP patients.

Oxygen uptake kinetics and middle distance swimming performance.

OBJECTIVE The aim of this study was to determine whether V˙O(2) kinetics and specifically, the time constant of transitions from rest to heavy (τ(p)H) and severe (τ(p)S) exercise intensities, are related to middle distance swimming performance. DESIGN Fourteen highly trained male swimmers (mean ± SD: 20.5 ± 3.0 yr; 75.4 ± 12.4 kg; 1.80 ± 0.07 m) performed an discontinuous incremental test, as well as square wave transitions for heavy and severe swimming intensities, to determine V˙O(2) kinetics parameters using two exponential functions. METHODS All the tests involved front-crawl swimming with breath-by-breath analysis using the Aquatrainer swimming snorkel. Endurance performance was recorded as the time taken to complete a 400 m freestyle swim within an official competition (T400), one month from the date of the other tests. RESULTS T400 (Mean ± SD) (251.4 ± 12.4 s) was significantly correlated with τ(p)H (15.8 ± 4.8s; r=0.62; p=0.02) and τ(p)S (15.8 ± 4.7s; r=0.61; p=0.02). The best single predictor of 400 m freestyle time, out of the variables that were assessed, was the velocity at V˙O(2max)vV˙O(2max), which accounted for 80% of the variation in performance between swimmers. However, τ(p)H and V˙O(2max) were also found to influence the prediction of T400 when they were included in a regression model that involved respiratory parameters only. CONCLUSIONS Faster kinetics during the primary phase of the V˙O(2) response is associated with better performance during middle-distance swimming. However, vV˙O(2max) appears to be a better predictor of T400.

Responses to static stretching are dependent on stretch intensity and duration.

Information regarding the effects of stretching intensity on the joint torque–angle response is scarce. The present study examined the effects of three static stretching protocols with different intensities and durations on the passive knee extension torque–angle response of seventeen male participants (age ± SD: 23·9 ± 3·6 years, height: 177·0 ± 7·2 cm, BMI: 22·47 ± 1·95 kg·m2). The stretching intensity was determined according to the maximal tolerable torque of the first repetition: fifty per cent (P50), seventy‐five per cent (P75) and the maximum intensity without pain (P100). Five repetitions were performed for each protocol. The stretch duration of each repetition was 90, 135 and 180 s for P100, P75 and P50, respectively. The rest period between repetitions was 30 s. Passive torque at a given angle, angle, stress relaxation, area under the curve, surface electromyography activity and visual analogue scale score were compared. The significant (P<0·05) results found were as follows: (i) the P50 and P75 did not increase the angle and passive peak torque outcomes, despite more time under stretch; (ii) only the P100 increased the angle and passive peak torque outcomes; (iii) the perception of stretching intensity mainly changed depending on knee angle changes, and not passive torque; (iv) the P50 induced a higher passive torque decrease; (v) when protocols were compared for the same time under stretch, the torque decrease was similar; (vi) the change in torque–angle curve shape was different depending on the stretching protocol. In conclusion, higher stretch duration seems to be a crucial factor for passive torque decrease and higher stretch intensity for maximum angle increase.

Are Rest Intervals between Stretching Repetitions Effective to Acutely Increase Range of Motion

UNLABELLED Static stretching with rest between repetitions is often performed to acutely increase joint flexibility. PURPOSE To test the effects of the lack of resting between stretching repetitions and the minimal number of stretching repetitions required to change the maximal range of motion (ROM), maximal tolerated joint passive torque (MPT), and submaximal passive torque at a given angle (PT). METHODS Five static stretching repetitions with a 30-s rest-interval (RI) and a no-rest-interval (NRI) stretching protocol were compared. Participants (N=47) were encouraged to perform the maximal ROM without pain in all the repetitions. Each repetition lasted 90 s. Maximal ROM, MPT, PT, and muscle activity were compared between protocols for the same number of stretching repetitions. RESULTS The NRI produced a higher increase in maximal ROM and MPT during and after stretching (P<.05). PT decreased in both protocols, although the NRI tended to have a lower decrement across different submaximal angles (.05<P<.08) in the initial range of the torque-angle curve. Significant changes in maximal ROM (P<.01) and PT (P<.01) were obtained at the 3rd and 2nd repetitions of RI, respectively. The RI did not significantly increase the MPT (P=.12) after stretching; only the NRI did (P<.01). CONCLUSIONS Lack of rest between repetitions more efficiently increased the maximal ROM and capacity to tolerate PT during and after stretching. The use of 30 s rest between repetitions potentiates the decrease in PT. Rest intervals should not be used if the aim is to acutely increase maximal ROM and peak passive torque.

Electromyographic Analysis of Trunk Muscles during the Golf Swing Performed with Two Different Clubs

The aim of this study was to compare the EMG patterns of trunk muscles throughout the golf swing, performed with two different clubs, and also to describe the activity patterns in the average golfer. Nine male golfers performed ten swings using the pitching wedge and the 4-iron, alternately. Surface electromyography (EMG) was recorded from trunk muscles of both sides: rectus abdominis (RA), external oblique (EO), erector spinae (ES) and gluteus maximus (GM). 3D high-speed video analysis was used for determination of golf swing phases. Muscles had their highest activation during the forward swing and acceleration phases. The highest mean activation regarding the maximal EMG (EMGMAX), was found in the right EO (59–67% EMGMAX) and in the GM of the trailing leg (62–72% EMGMAX). In the majority of the cases and phases, trunk muscles showed higher mean values of EMG activation when golfers performed with 4-iron club. However, no club effect was verified in trunk muscles.

Provocative mechanical tests of the peripheral nervous system affect the joint torque-angle during passive knee motion

This study aimed to determine the influence of the head, upper trunk, and foot position on the passive knee extension (PKE) torque‐angle response. PKE tests were performed in 10 healthy subjects using an isokinetic dynamometer at 2°/s. Subjects lay in the supine position with their hips flexed to 90°. The knee angle, passive torque, surface electromyography (EMG) of the semitendinosus and quadriceps vastus medialis, and stretch discomfort were recorded in six body positions during PKE. The different maximal active positions of the cervical spine (neutral; flexion; extension), thoracic spine (neutral; flexion), and ankle (neutral; dorsiflexion) were passively combined for the tests. Visual analog scale scores and EMG were unaffected by body segment positioning. An effect of the ankle joint was verified on the peak torque and knee maximum angle when the ankle was in the dorsiflexion position (P < 0.05). Upper trunk positioning had an effect on the knee submaximal torque (P < 0.05), observed as an increase in the knee passive submaximal torque when the cervical and thoracic spines were flexed (P < 0.05). In conclusion, other apparently mechanical unrelated body segments influence torque‐angle response since different positions of head, upper trunk, and foot induce dissimilar knee mechanical responses during passive extension.

Stretching Effects: High-intensity & Moderate- duration vs. Low-intensity & Long-duration

This study examined whether a high-intensity, moderate-duration bout of stretching would produce the same acute effects as a low-intensity, long-duration bout of stretching. 17 volunteers performed 2 knee-flexor stretching protocols: a high-intensity stretch (i. e., 100% of maximum tolerable passive torque) with a moderate duration (243.5 ± 69.5-s); and a low-intensity stretch (50% of tolerable passive torque) with a long duration (900-s). Passive torque at a given sub-maximal angle, peak passive torque, maximal range of motion (ROM), and muscle activity were assessed before and after each stretching protocol (at intervals of 1, 30 and 60 min). The maximal ROM and tolerable passive torque increased for all time points following the high-intensity stretching (p<0.05), but not after the low-intensity protocol (p>0.05). 1 min post-stretching, the passive torque decreased in both protocols, but to a greater extent in the low-intensity protocol. 30 min post-test, torque returned to baseline for the low-intensity protocol and had increased above the baseline for the high-intensity stretches. The following can be concluded: 1) High-intensity stretching increases the maximal ROM and peak passive torque compared to low-intensity stretching; 2) low-intensity, long-duration stretching is the best way to acutely decrease passive torque; and 3) high-intensity, moderate-duration stretching increases passive torque above the baseline 30 min after stretching.

Body composition, muscle strength, functional capacity, and physical disability risk in liver transplanted familial amyloidotic polyneuropathy patients

Tomás MT, Santa‐Clara MH, Monteiro E, Baynard T, Carnero EÁ, Bruno PM, Barroso E, Sardinha LB, Fernhall B. Body composition, muscle strength, functional capacity, and physical disability risk in liver transplanted familial amyloidotic polyneuropathy patients.
Clin Transplant 2011: 25: E406–E414.

Ventilatory and Physiological Responses in Swimmers Below and Above Their Maximal Lactate Steady State.

Abstract Espada, MC, Reis, JF, Almeida, TF, Bruno, PM, Vleck, VE, and Alves, FB. Ventilatory and physiological responses in swimmers below and above their maximal lactate steady state. J Strength Cond Res 29(10): 2836–2843, 2015—The purpose of this study was to understand the ventilatory and physiological responses immediately below and above the maximal lactate steady-state (MLSS) velocity and to determine the relationship of oxygen uptake (V[Combining Dot Above]O2) kinetics parameters with performance, in swimmers. Competitive athletes (N = 12) completed in random order and on different days a 400-m all-out test, an incremental step test comprising 5 × 250- and 1 × 200-m stages and 30 minutes at a constant swimming velocity (SV) at 87.5, 90, and 92.5% of the maximal aerobic velocity for MLSS velocity (MLSSv) determination. Two square-wave transitions of 500 m, 2.5% above and below the MLSSv were completed to determine V[Combining Dot Above]O2 on-kinetics. End-exercise V[Combining Dot Above]O2 at 97.5 and 102.5% of MLSSv represented, respectively, 81 and 97% of V[Combining Dot Above]O2max; the latter was not significantly different from maximal V[Combining Dot Above]O2 (V[Combining Dot Above]O2max). The V[Combining Dot Above]O2 at MLSSv (49.3 ± 9.2 ml·kg−1·min−1) was not significantly different from the second ventilatory threshold (VT2) (51.3 ± 7.6 ml·kg−1·min−1). The velocity associated with MLSS seems to be accurately estimated by the SV at VT2 (vVT2), and vV[Combining Dot Above]O2max also seems to be estimated with accuracy from the central 300-m mean velocity of a 400-m trial, indicators that represent a helpful tool for coaches. The 400-m swimming performance (T 400) was correlated with the time constant of the primary phase V[Combining Dot Above]O2 kinetics (&tgr;p) at 97.5% MLSSv, and T 800 was correlated with &tgr;p in both 97.5 and 102.5% of MLSSv. The assessment of the V[Combining Dot Above]O2 kinetics in swimming can help coaches to build training sets according to a swimmer’s individual physiological response.

Sex and Exercise Intensity Do Not Influence Oxygen Uptake Kinetics in Submaximal Swimming

The aim of this study was to compare the oxygen uptake (V˙O2) kinetics in front crawl between male and female swimmers at moderate and heavy intensity. We hypothesized that the time constant for the primary phase V˙O2 kinetics was faster in men than in women, for both intensities. Nineteen well trained swimmers (8 females mean ± SD; age 17.9 ± 3.5 years; mass 55.2 ± 3.6 kg; height 1.66 ± 0.05 m and 11 male 21.9 ± 2.8 years; 78.2 ± 11.1 kg; 1.81 ± 0.08 m) performed a discontinuous maximal incremental test and two 600-m square wave transitions for both moderate and heavy intensities to determine the V˙O2 kinetics parameters using mono- and bi-exponential models, respectively. All the tests involved breath-by-breath analysis of front crawl swimming using a swimming snorkel. The maximal oxygen uptake (V˙O2max) was higher in men than in women [4,492 ± 585 ml·min−1 and 57.7 ± 4.4 ml·kg−1·min−1 vs. 2,752.4 ± 187.9 ml·min−1 (p ≤ 0.001) and 50.0 ± 5.7 ml·kg−1·min−1(p = 0.007), respectively]. Similarly, the absolute amplitude of the primary component was higher in men for both intensities (moderate: 1,736 ± 164 vs. 1,121 ± 149 ml·min−1; heavy: 2,948 ± 227 vs. 1,927 ± 243 ml·min−1, p ≤ 0.001, for males and females, respectively). However, the time constant of the primary component (τp) was not influenced by sex (p = 0.527) or swimming intensity (p = 0.804) (moderate: 15.1 ± 5.6 vs. 14.4 ± 5.1 s; heavy: 13.5 ± 3.3 vs. 16.0 ± 4.5 s, for females and males, respectively). The slow component in the heavy domain was not significantly different between female and male swimmers (3.2 ± 2.4 vs. 3.8 ± 1.0 ml·kg−1·min−1, p = 0.476). Overall, only the absolute amplitude of the primary component was higher in men, while the other V˙O2 kinetics parameters were similar between female and male swimmers at both moderate and heavy intensities. The mechanisms underlying these similarities remain unclear.