The combination of endurance training and strength training makes fat people slimmer and healthier, and works better than cardio or strength training alone, we wrote yesterday. Putting together a good combo-training schedule is not easy though. Endurance training and strength training reduce each other’s effect. A new piece of fundamental research published in the Journal of Strength and Conditioning Research by British sports scientists at Northumbria University confirms this.
The combination of endurance training and strength training makes fat people slimmer and healthier, and works better than cardio or strength training alone, we wrote yesterday. Putting together a good combo-training schedule is not easy though. Endurance training and strength training reduce each other’s effect. A new piece of fundamental research published in the Journal of Strength and Conditioning Research by British sports scientists at Northumbria University confirms this.
The researchers did their experiment on 24 men, average age 25, all of whom had been doing recreational weight training for at least two years.
The researchers got most of the men to train on a leg-extension machine 3 times a week for 6 weeks. A small group did no training and functioned as the control group [Control; CON].
The researchers got one group of men to train their quads, doing 5 sets at a weight with which they could just manage 6 reps [Strength training; ST].
A second experimental group did endurance training once a week after the strength training [Str/end training 3:1, CT3]. The endurance training consisted of leg-extensions too, but these were done using a weight with which the participants could keep going for half an hour.
A third experimental group did endurance training after each weight training session [Str/end training 1:1, CT1].
At the end of the six weeks, the researchers saw that the men who had done strength training only had become stronger. The men who combined strength training and endurance training had also gained strength, but less than the first group had done.
The figure below shows that in the group that did endurance training after each strength training session the increase in strength was almost nil.
The figure above shows that endurance training also reduced the effect of strength training on muscle girth. The more endurance training the men had done, the less their muscles had grown.
At the end of the six weeks the researchers also measured how long the men could keep going with leg extensions using low weights [Time to exhaustion]. Adding endurance training to strength training had a positive effect on this parameter.
The figure below summarises the research findings.
“If […] strength and hypertrophy are the primary aims frequency and volume of endurance components should conceivably remain low as it seems that increased volumes of endurance training results in amplified inhibition of strength and muscular growth responses”, the Brits conclude. “As such, practitioners involved in sports and events that require both strength and endurance capabilities should carefully monitor the volume of endurance training prescribed if interference is to be avoided.”
Performance and neuromuscular adaptations following differing ratios of concurrent strength and endurance training.
Jones TW, Howatson G, Russell M, French DN.
Abstract
The interference effect attenuates strength and hypertrophic responses when strength and endurance training are conducted concurrently; however, the influence of training frequency on these responses remain unclear when varying ratios of concurrent strength and endurance training are performed. Therefore, the purpose of the study was to examine the strength, limb girth, and neuromuscular adaptations to varying ratios of concurrent strength and endurance training. Twenty-four men with >2 years resistance training experience completed 6 weeks of 3 days per week of (a) strength training (ST), (b) concurrent strength and endurance training ratio 3:1 (CT3), (c) concurrent strength and endurance training ratio 1:1 (CT1), or (d) no training (CON) in an isolated limb model. Assessments of maximal voluntary contraction by means of isokinetic dynamometry leg extensions (maximum voluntary suppression [MVC]), limb girth, and neuromuscular responses through electromyography (EMG) were conducted at baseline, mid-intervention, and postintervention. After training, ST and CT3 conditions elicited greater MVC increases than CT1 and CON conditions (p ? 0.05). Strength training resulted in significantly greater increases in limb girth than both CT1 and CON conditions (p = 0.05 and 0.004, respectively). The CT3 induced significantly greater limb girth adaptations than CON condition (p = 0.04). No effect of time or intervention was observed for EMG (p > 0.05). In conclusion, greater frequencies of endurance training performed increased the magnitude of the interference response on strength and limb girth responses after 6 weeks of 3 days a week of training. Therefore, the frequency of endurance training should remain low if the primary focus of the training intervention is strength and hypertrophy.
PMID: 24270456 [PubMed – in process]
