Functional vs. dual-task training effects on trunk muscle function and functional fitness in older women with and without chronic low back pain: A randomized clinical trial.

INTRODUCTION: Non-specific chronic low back pain (CLBP) predominantly affects women aged 40-80 years. Physical exercise is a primary treatment form, with functional training (FT) and dual-task training (DT) emerging as potential modalities due to their distinct characteristics. However, limited information exists regarding the effects of these exercise modalities on CLBP. OBJECTIVE: To compare the FT and DT effects on trunk function and functional fitness in CLBP older women. METHODOLOGY: This was a randomized clinical trial with two training groups (FT and DT) and CLBP and non-CLBP individuals. We assessed the trunk stability, maximum isometric strength, endurance of trunk muscles, and functional fitness before and after 16 weeks of training RESULTS: We found only time effects for circular stability and instability (p <.001), flexors (p =.006), and extensors endurance (p <.001). For the lateral flexors, there was an average reduction of 17.3 units in lateral flexor endurance in the FT compared to the DT in CLBP individuals. For the strength of the flexor, CLBP individuals exhibited an increase of 69.3 units compared to non-CLBP. For the strength of extensors, CLBP individuals showed a decrease of 75.1 units compared to non-CLBP individuals. We identified a time effect for all functional fitness measures (p <.050) CONCLUSION: FT and DT increase trunk stability, maximum isometric strength, and endurance of trunk muscles, besides the functional fitness of CLBP older women SIGNIFICANCE: Professionals can choose either training type, as there are no differences in the initial 16 weeks of intervention.

Interferential current intensity influences the hypoalgesic response in healthy subjects under mechanically-induced pain: A randomized controlled trial.

BACKGROUND: Interferential current (IFC) is a non-pharmacological therapy often used to reduce pain intensity. However, there is no scientific evidence of the biological effects of the adjustment of IFC intensity of stimulation. OBJECTIVE: To investigate whether the adjustment of IFC intensity influences pain on cutaneous sensory threshold (CST), pressure pain threshold (PPT) and pain intensity in healthy subjects under mechanically induced pain. METHODS: This is a placebo-controlled randomized trial. One hundred and two healthy university students blinded to intervention were randomized using opaque sealed envelopes to the following groups: 1) sensory IFC (n = 24); 2) fixed motor IFC (n = 26); 3) adjusted motor IFC (n = 27); and 4) placebo IFC (n = 25). After 40 minutes of stimulation or placebo, subjects were evaluated by an investigator blinded to group allocation. CST (von Frey filaments), PPT (algometry), and pain intensity (11-point numerical scale) were measured. RESULTS: Adjusted motor IFC promoted a significant reduction of CST (hand: mean difference (MD) = 2.39, confidence intervals (CI) = 1.39-3.38; and forearm: MD = 3.01, CI = 2.87-3.14) compared to placebo. Adjusted motor IFC increased PPT significantly (hand: MD = 27.59, CI = 26.80-28.37; and forearm: MD = 34, CI = 25.74-42.25) when compared to placebo. Adjusted motor IFC reduced pain intensity by 4.01 points (CI = 3.64-4.55) when compared to placebo. No adverse events were observed. CONCLUSIONS: Adjusted motor IFC intensity increased PPT and CST and also reduced pain intensity in healthy subjects under mechanically induced pain.