The aim of this study was to investigate the effects of two consecutive extreme conditioning program training sessions (24 h apart) designed to enhance work-capacity that involved both cardiovascular and muscular exercises on cytokines, muscle power, blood lactate and glucose. Nine male members of the extreme conditioning community (age 26.7 ± 6.6 years; body mass 78.8 ± 13.2 kg; body fat 13.5 ± 6.2%; training experience 2.5 ± 1.2 years) completed two experimental protocols (24 h apart): (1) strength and power exercises, (2) gymnastic movements, and (3) metabolic conditioning as follows: 10 min of as many rounds as possible (AMRAP) of 30 double-unders and 15 power snatches (34 kg). The same sequence as repeated on session 2 with the following metabolic conditioning: 12 min AMRAP of: row 250 m and 25 target burpees. Serum interleukin-6 (IL-6), IL-10, and osteoprotegerin were measured before, immediately post and 24 h after workout of the day (WOD) 1, immediately post, 24 and 48 h after WOD 2. Peak and mean power were obtained for each repetition (back squat with 50% of 1 repetition maximum) using a linear position transducer measured before, immediately post and 24 h after WOD 1, immediately post and 24 h after WOD 2. Blood lactate and glucose were measured pre and immediately post WOD 1 and 2. Although both sessions of exercise elicited an significant increase in blood lactate (1.20 ± 0.41 to 11.84 ± 1.34 vs. 0.94 ± 0.34 to 9.05 ± 2.56 mmol/l) and glucose concentration (81.59 ± 10.27 to 114.99 ± 12.52 vs. 69.47 ± 6.97 to 89.95 ± 19.26 mg/dL), WOD 1 induced a significantly greater increase than WOD 2 (p ≤ 0.05). The training sessions elicited significant changes (p ≤ 0.05) in IL-6, IL-10 and osteoprotegerin concentration over time. IL-6 displayed an increase immediately after training WOD 1 [197 ± 109%] (p = 0.009) and 2 [99 ± 58%] (p = 0.045). IL-10 displayed an increase immediately after only WOD 1 [44 ± 52%] (p = 0.046), and decreased 24 and 48 h following WOD 2 (~40%; p = 0.018) as compared to pre-exercise values. Osteoprotegerin displayed a decrease 48 h following WOD 2 (~25%; p = 0.018) as compared with pre intervention. In conclusion, two consecutive extreme conditioning training sessions increase pro/anti-inflammatory cytokines with no interference on muscle performance in the recovery period.

The purpose of the present study was to compare the longitudinal effects of six weeks of rest-pause versus traditional multiple-set RT on muscle strength, hypertrophy, localized muscular endurance, and body composition in trained subjects. Eighteen trained subjects (mean ± SD; age = 30.2 ± 6.6 years; weight = 74.8 ± 17.2 kg; height = 171.4 ± 10.3 cm) were randomly assigned to either a traditional multiple-set group (n = 9; 7 males and 2 females; 3 sets of 6 repetitions with 80% of 1-RM and 2 min rest intervals between sets) or a rest-pause group (n = 9; 7 males and 2 females). The results showed no significant differences (p > 0.05) between groups in 1RM strength (rest-pause: 16 ± 11% for BP, 25 ± 17% for LP, and 16 ± 10% for BC versus traditional multiple-set: 10 ± 21% for BP, 30 ± 20% for LP and 21 ± 20% for BC). In localized muscular endurance, the rest-pause group displayed significantly greater (p < 0.05) repetitions, only for the LP exercise (rest pause: 27 ± 8% versus traditional multiple set: 8 ± 2%). In muscle hypertrophy, the rest-pause group displayed significantly greater (p < 0.05) thickness, only for the thigh (rest-pause: 11 ± 14% versus traditional multiple-set: 1 ± 7%). In conclusion, resistance training performed with the rest-pause method resulted in similar gains in muscle strength as traditional multiple-set training. However, the rest-pause method resulted in greater gains in localized muscular endurance and hypertrophy for the thigh musculature.

Despite its increase in popularity, little is known about how to best quantify internal training loads from functional fitness training (FFT) sessions. The purpose of this study was to assess which method [training impulse (TRIMP) or session rating of perceived exertion (sRPE)] is more accurate to monitor training loads in FFT. Eight trained males (age 28.1 ± 6.0 years) performed an ALL-OUT FFT session and an intensity-controlled session (RPE of six out of 10). Internal load was determined via Edward’s TRIMP (eTRIMP), Bannister’s TRIMP (bTRIMP), and sRPE. Heart rate was measured continuously during the session, while blood lactate and rate of perceived exertion were measured at baseline, and immediately and 30 min after the sessions. ALL-OUT blood lactate and RPE were significantly higher immediately and 30 min after the session compared to the RPE6 condition. ALL-OUT training load was significantly different between conditions using bTRIMP (61.1 ± 10.6 vs. 55.7 ± 12.4 AU) and sRPE (91.7 ± 30.4 vs. 42.6 ± 14.9 AU), with sRPE being more sensitive to such differences [ p = 0.045, effect size (ES) = 0.76 and p = 0.002, ES = 1.82, respectively]. No differences in the training loads of the different sessions were found using eTRIMP (93.1 ± 9.5 vs. 84.9 ± 13.7 AU, p = 0.085). Only sRPE showed a significant correlation with lactate 30 min post session ( p = 0.015; p = 0.596, large). sRPE was more accurate than both TRIMP methods to represent the overall training load of the FFT sessions. While the use of sRPE is advised, further research is necessary to establish its ability to reflect changes in fitness, fatigue, and performance during a period of training.

This study provides insights that a high pro-inflammatory status in sedentary obese elderly women might impair muscle strength and negatively affect fat-free mass. Thus, elderly women classified with high pro-inflammatory status for IL-6 should receive further health care attention to prevent this deleterious condition.

Background: Trained subjects have difficulty in achieving continued results following years of training, and the manipulation of training variables through advanced resistance training (RT) methods is widely recommended to break through plateaus. Objective: The purpose of the present study was to compare the acute effects of traditional RT (TRT) versus two types of sarcoplasma stimulating training (SST) methods on total training volume (TTV), lactate, and muscle thickness (MT). Methods: Twelve trained males (20.75 ± 2.3 years; 1.76 ± 0.14 meters; body mass = 79.41 ± 4.6 kg; RT experience = 4.1 ± 1.8 years) completed three RT protocols in a randomly sequenced order: TRT, SST contraction type (SST-CT), or SST rest interval variable (SST-RIV) with 7 days between trials in arm curl (elbow flexors) and triceps pulley extension (elbow extensors) performed on the same day. Results: The SST groups displayed greater acute biceps and triceps brachii (TB) MT versus the TRT session, with no difference in lactate levels between them. The SST-CT resulted in greater biceps and TB MT versus the SST-RIV session. The TTV was greater for the TRT session versus the SST sessions, except in the case of the elbow flexors (no difference was observed between TRT and SST-CT), and higher for the SST-CT versus the SST-RIV. Conclusion: Trained subjects may benefit from using the SST method as this method may offer a superior MT stimulus and reduced training time, even with a lower TTV.