You will be presented with a collection of medical randomized controlled trial (RCT) reports addressing a shared clinical question -- for instance, the efficacy of a medical intervention on a disease or condition. Given the titles and abstracts of these reports, your task is to generate the conclusion of the systematic review article synthesizing the key findings. Your conclusion should be a few sentences long. In your response, include only the conclusion and no other text. The RCT reports are below.



Title 1:
Hemodynamic Responses to Resistance Exercise in Patients with Coronary Artery Disease.
Abstract 1:
PURPOSE Investigate hemodynamic responses of resistance exercise ( RE ) with moderate load ( i.e. , international guidelines for RE of patients ) versus RE with high load in patients with coronary artery disease ( CAD ) . METHODS Medically stable male ( n = 11 ) and female patients ( n = 4 ) treated with PCI or percutaneous coronary intervention , or coronary artery bypass surgery a minimum of 6 months before this study , performed three sets of 15RM and 4RM RE in a r and omized order on separate days . Beat-to-beat systolic ( SBP ) , diastolic ( DBP ) blood pressure , heart rate ( HR ) , stroke volume ( SV ) , cardiac output ( CO ) , and systemic vascular resistance ( SVR ) were monitored at preexercise , and continuously during RE . RESULTS Compared with preexercise , SBP and DBP ( mean of three sets ) increased by 12 % to 13 % ( both ; P < 0.001 ) and 35 % to 40 % after 15RM RE ( both ; P < 0.001 ) . 15RM SBP and DBP were higher than 4RM SBP and DBP ( both ; P < 0.001 ) . The SBP of the fourth repetition of 15 RM RE was similar to the SBP of the fourth repetition of 4RM RE . Compared with preexercise , SV increased moderately after 4RM and 15 RM RE , respectively ( both , P < 0.001 ) . HR increased more after 15RM compared with 4RM RE ( P < 0.05 ) ; thus , higher CO after 15RM ( compared with 4RM RE ; P < 0.05 ) was mainly caused by higher HR . SVR decreased by 15 % ( P < 0.001 ) and 50 % ( P < 0.01 ) after 4RM and 15RM RE . CONCLUSIONS SBP and DBP increased significantly more during moderate load RE ; thus , the magnitude of the external load is not the prime determinant of the pressure response during RE . If management of blood pressure is of concern , high load/low rep RE is preferable to medium load/high rep RE


Title 2:
Intra-Arterial Blood Pressure Response in Hypertensive Subjects during Low- and High-Intensity Resistance Exercise
Abstract 2:
OBJECTIVE : The aim of this study was to describe blood pressure responses during resistance exercise in hypertensive subjects and to determine whether an exercise protocol alters these responses . INTRODUCTION : Resistance exercise has been recommended as a complement for aerobic exercise for hypertensive patients . However , blood pressure changes during this kind of exercise have been poorly investigated in hypertensives , despite multiple studies of normotensives demonstrating significant increases in blood pressure . METHODS : Ten hypertensive and ten normotensive subjects performed , in r and om order , two different exercise protocol s , composed by three sets of the knee extension exercise conducted to exhaustion : 40 % of the 1-repetition maximum ( 1RM ) with a 45-s rest between sets , and 80 % of 1RM with a 90-s rest between sets .  Radial intra-arterial blood pressure was measured before and throughout each protocol . RESULTS : Compared with normotensives , hypertensives displayed greater increases in systolic BP during exercise at 80 % ( + 80±3 vs. + 62±2 mmHg , P<0.05 ) and at 40 % of 1RM ( + 75±3 vs. + 67±3 mmHg , P<0.05 ) . In both exercise protocol s , systolic blood pressure returned to baseline during the rest periods between sets in the normotensives ; however , in the hypertensives , BP remained slightly elevated at 40 % of 1RM . During rest periods , diastolic blood pressure returned to baseline in hypertensives and dropped below baseline in normotensives . CONCLUSION : Resistance exercise  increased systolic blood pressure considerably more in hypertensives than in normotensives , and this increase was greater when lower-intensity exercise was performed to the point of exhaustion


Title 3:
The effect of different intensity modalities of resistance training on beat-to-beat blood pressure in cardiac patients.
Abstract 3:
BACKGROUND Resistance training has been introduced in cardiac rehabilitation to give more benefit than traditional training . Haemodynamic evaluation of cardiac patients to resistance training has generally consisted of continuous HR monitoring and discontinuous blood pressure measurements . DESIGN AND METHODS Blood pressure ( BP ) and heart rate ( HR ) responses to resistance training were evaluated using continuous monitoring ( Finapres ) during low ( four sets of 17 repetitions at 40 % of the one-repetition maximum strength [ 1-RM ] ) and high intensity resistance training ( four sets of 10 repetitions at 70 % of 1-RM ) on a leg extension machine in 14 patients who participated in a rehabilitation programme .  Work volume was identical in the low- and high-level resistance training . RESULTS The HR and systolic blood pressure ( SBP ) during low intensity resistance training were always larger than during high intensity ( P<0.001 ) . Peak SBP increased from set 1 to set 3 and 4 during both low and high intensity resistance training ( P<0.05 ) . Peak HR was larger in set 4 ( 95+/-11 bpm ) than in set 1 only during low intensity resistance training ( 91+/-12 bpm ) ( P<0.05 ) . One-minute recovery periods did not allow a return to baseline HR and SBP during both low and high intensity modalities . CONCLUSIONS The SBP and HR responses to resistance training are related to the duration of exercise . Sets with < or = 10 repetitions of high intensity should be preferred to longer sets with low intensity . Pauses between exercise sets should exceed 1 min . Blood pressure should be measured during the last repetitions of the exercise set


Title 4:
Acute hemodynamic and cardiovascular responses following resistance exercise to voluntary exhaustion. Effects of different loadings and exercise durations.
Abstract 4:
BACKGROUND The aim of this study was to compare the acute hemodynamic and cardiovascular responses of high load/low repetition resistance training ( RT ) to low load/high repetition RT . METHODS Thirteen healthy men performed four sets of 4 repetition maximum ( RM ) and 20RM leg-extensions without breath-holding . The RT was conducted in a r and omized order and with 48 hours between bouts . Non-invasive  beat-to-beat systolic and diastolic blood-pressure ( SBP/DBP ) was measured on the finger , while non-invasive cardiac output ( CO ) was assessed beat-to-beat by impedance-cardiography . RESULTS Mean±SD resting SBP/DBP and CO were 126±14/73±9 mmHg and 5.6±9 L min-1 , respectively . Exercise SBP/DBP values increased to 154±22/99 ±18 and 203±33/126±19 mmHg following 4RM and 20RM RT , respectively ( compared to rest , all ; P<0.001 ) , and 20RM SBP/DBP values were higher than 4RM values ( both , P<0.001 ) . The SBP increased from the first to the fourth set of exercise following the 20RM load ( P<0.01 ) , but not so for the 4RM load . Exercise SBP/DBP values following the 4th rep of 20RM exercise ( 154±18/91±14 ) , was similar to the 4RM values , but different to the 20th rep of the 20 RM loading ( both ; P<0.001 ) . CO increased to 10.8±2.6 and 13.9±2.2 L min-1 , following 4RM and 20RM RT , respectively ( compared to rest , both ; P<0.001 ) and 20RM CO was higher than 4RM CO ( P<0.01 ) . CONCLUSIONS 20RM RT result ed in higher blood-pressure  than 4RM RT when performed to voluntary exhaustion . Differences in hemodynamic responses seems to be related to training duration and not to difference in loading


Title 5:
Greater Neural Adaptations following High- vs. Low-Load Resistance Training
Abstract 5:
We examined the neuromuscular adaptations following 3 and 6 weeks of 80 vs. 30 % one repetition maximum ( 1RM ) resistance training to failure in the leg extensors . Twenty-six men ( age = 23.1 ± 4.7 years ) were r and omly assigned to a high- ( 80 % 1RM ; n = 13 ) or low-load ( 30 % 1RM ; n = 13 ) resistance training group and completed leg extension resistance training to failure 3 times per week for 6 weeks . Testing was completed at baseline , 3 , and 6 weeks of training . During each testing session , ultrasound muscle thickness and echo intensity , 1RM strength , maximal voluntary isometric contraction ( MVIC ) strength , and contractile properties of the quadriceps femoris were measured . Percent voluntary activation ( VA ) and electromyographic ( EMG ) amplitude were measured during MVIC , and during r and omly ordered isometric step muscle actions at 10–100 % of baseline MVIC . There were similar increases in muscle thickness from Baseline to Week 3 and 6 in the 80 and 30 % 1RM groups . However , both 1RM and MVIC strength increased from Baseline to Week 3 and 6 to a greater degree in the 80 % than 30 % 1RM group . VA during MVIC was also greater in the 80 vs. 30 % 1RM group at Week 6 , and only training at 80 % 1RM elicited a significant increase in EMG amplitude during MVIC . The peak twitch torque to MVIC ratio was also significantly reduced in the 80 % , but not 30 % 1RM group , at Week 3 and 6 . Finally , VA and EMG amplitude were reduced during submaximal torque production as a result of training at 80 % 1RM , but not 30 % 1RM . Despite eliciting similar hypertrophy , 80 % 1RM improved muscle strength more than 30 % 1RM , and was accompanied by increases in VA and EMG amplitude during maximal force production . Furthermore , training at 80 % 1RM result ed in a decreased neural cost to produce the same relative submaximal torques after training , whereas training at 30 % 1RM did not . Therefore , our data suggest that high-load training results in greater neural adaptations that may explain the disparate increases in muscle strength despite similar hypertrophy following high- and low-load training programs


Title 6:
Aerobic and resistance training in coronary disease: single versus multiple sets.
Abstract 6:
PURPOSE The purpose of this study was to compare resistance training ( RT ) ( one set vs three sets ) combined with aerobic training ( AT ) versus AT alone in persons with coronary artery disease . METHODS Subjects ( n = 72 ) were r and omized to AT ( 5 d x wk(-1 ) ) or combined AT ( 3 d x wk(-1 ) ) with either one set ( AT/RT1 ) or three sets ( AT/RT3 ) of RT performed 2 d x wk(-1 ) . VO2peak , ventilatory anaerobic threshold ( VAT ) , strength and endurance , body composition , and adherence were measured before and after 29 wk of training . RESULTS Fifty-three subjects ( mean + /- SEM age 61 + /- 2 ) completed the training . The increase from baseline in VO2peak ( L x min(-1 ) ) averaged 11 % for AT ( P < 0.05 ) , 14 % for AT/RT1 ( P < 0.01 ) , and 18 % for AT/RT3 ( P < 0.001 ) , however , the difference between groups was not significant . VAT improved significantly in the AT/RT3 group only ( P < 0.05 ) . The AT/RT3 group gained more lean mass than the AT group ( 1.5 versus 0.4 kg , P < 0.01 ) , yet gains between AT/RT1 and AT were similar ( P = 0.2 ) . Only AT + RT groups demonstrated a reduction in body fat ( P < 0.05 ) . Strength and endurance increased more in the AT + RT groups than AT alone ( P < 0.05 ) . Adherence to number of sets performed was lower in AT/RT3 than AT/RT1 ( P < 0.02 ) . CONCLUSIONS Combined AT + RT yields more pronounced physiological adaptations than AT alone and appears to be superior in producing improvements in VO2peak , muscular strength and endurance , and body composition . The data support the use of multiple set RT for patients desiring an increased RT stimulus which may further augment parameters that affect VO2peak , VAT , lower body endurance , and muscle mass in a cardiac population
When added to endurance training , dynamic strength training leads to significantly greater improvements in peripheral muscle strength and power output in patients with cardiovascular disease , which may be relevant to enhance the patient ’s prognosis .
Moreover , multiple studies report that high-intensity strength training causes fewer increments in (intra-)arterial blood pressure and cardiac output , as opposed to low-intensity strength training , thus potentially pointing towards sufficient medical safety for the cardiovascular system .