LOAD-intensity and time-under-tension of exercises for men who have Achilles tendinopathy (the LOADIT trial): a randomised feasibility trial

Abstract

Background One potential reason for disparate outcomes of exercise for Achilles tendinopathy is poor knowledge about whether exercise parameters (i.e. different exercise doses) influence outcome. Whether parameters that are important for tendon adaptation influence clinical outcomes in Achilles tendinopathy has not been investigated. Therefore, this research aimed to assess the feasibility of conducting a fully powered randomised trial to investigate the efficacy of different load-intensity and time-under-tension exercise parameters for Achilles tendinopathy. Methods A factorial four-arm, randomised trial. Forty-eight male participants (18–70 years old) with mid-portion Achilles tendinopathy (≥ 3 months) were recruited. Participants were randomly allocated to high (6 repetition maximum) or low intensity (18 repetition maximum) exercise, performed with either high (6 s per cycle) or low (2 s per cycle) time-under-tension. Participants performed 12-weeks of standing and seated calf raise exercises three times per week in a gym setting using a Smith machine. One session per week was supervised (via videoconference). Primary feasibility outcomes (recruitment and retention rate, exercise adherence and fidelity [i.e. time-under-tension, volume, load intensity], incidence of adverse events, health care use and productivity cost) were collected weekly. Means and standard deviations were determined for parametric data, medians and interquartile range for non-parametric continuous data, and frequency counts for discrete data. Results Total recruitment (76%) and retention (90%) rates were high. Exercise adherence ranged from 45 to 63% and fidelity ranged from 8 to 83% across the groups. Thirty-one participants reported 64 adverse events over the 3 months. Twenty-one participants (70%) reported mild events. Participants reported reduced presenteeism more than absenteeism. Conclusions A fully powered trial is feasible. The proposed trial design and interventions demonstrated acceptable recruitment and retention rates and safety profile. However, exercise fidelity and adherence to the gym-based intervention was not acceptable. Strategies to improve intervention adherence and fidelity should be considered in future trials. Trial registration Australian New Zealand Clinical Trials Registry, ACTRN12618001315202. Registered retrospectively on August 6th, 2018.

Assessment of the reporting quality of resistance training interventions in randomised controlled trials for lower limb tendinopathy: A systematic review

“…Only 7 (6%) studies achieved a full 13/13 for reporting items from the framework. [16][17][18][19][20][21][22] Overall reporting across all studies for each item is presented in Figure 2. Only 3 items were reported by less than 80% of studies, rest between sets (26%), time under tension (23%) and volitional muscular failure (7%).…”

“…Of the 19 items included in the CERT, reporting among included studies ranged from 0-18, with an average score of 14/19 (for full data see S6). No study achieved a full score of 19, but5 17,20,21,23,24 (5%) studies achieved a high score of 18/19, of these,3 17,20,21 also achieved a full score of 13/13 for reporting exercise descriptors. Overall reporting for included studies is presented in Figure 3.…”

“…Out of the 7 items of the i-CONTENT tool, reporting across studies ranged from 2-7, with an average score of 5 across included studies (for full data see S7). A total of 19 16,17,[19][20][21]23,24,[26][27][28][29][30][31][32][33][34][35][36][37][38] studies achieved a full 7/7 score for the i-CONTENT tool with three of these achieving 18/19 for the CERT and 13/13 for the Toigo and Boutellier framework also. 17,20,21 Overall reporting for each item is presented in Figure 4.…”

“…A total of 19 16,17,[19][20][21]23,24,[26][27][28][29][30][31][32][33][34][35][36][37][38] studies achieved a full 7/7 score for the i-CONTENT tool with three of these achieving 18/19 for the CERT and 13/13 for the Toigo and Boutellier framework also. 17,20,21 Overall reporting for each item is presented in Figure 4. The item with the lowest level of reporting was adherence to the exercise programme, which was only reported in 39 studies (36%).…”

Foundational Principles and Adaptation of the Healthy and Pathological Achilles Tendon in Response to Resistance Exercise: A Narrative Review and Clinical Implications

“…HSR, which maximally reaches six RM, has been adapted for AT and has demonstrated clinical benefits while also being well received by patients [ 35 ]. However, more research for HSR is required [ 142 ], and adherence and fidelity to exercise dose during HSR in individuals with AT may pose an issue [ 148 ]. Additionally, the importance of load progression for AT rehabilitation cannot be overstated [ 1 , 2 , 41 , 149 ].…”